1

By its appeal, the Republic of Poland seeks, first, to have set aside the judgment of the General Court of 29 May 2024, Poland v Commission (T‑200/22 and T‑314/22, ‘the judgment under appeal’, EU:T:2024:329), by which the General Court dismissed its actions against the decisions of the European Commission of 7 and 8 February 2022, of 16 and 31 March 2022 and of 16 May 2022 (together, ‘the decisions at issue’), by which the Commission recovered, by way of set-off, the amounts payable by the Republic of Poland in respect of the daily penalty payment ordered by the Vice-President of the Court of Justice in her order of 20 September 2021, Czech Republic v Poland (C‑121/21 R, ‘the order of 20 September 2021’, EU:C:2021:752), and, second, the annulment of the decisions at issue.

2

Article 259 TFEU provides:

‘A Member State which considers that another Member State has failed to fulfil an obligation under the Treaties may bring the matter before the Court of Justice of the European Union.

Before a Member State brings an action against another Member State for an alleged infringement of an obligation under the Treaties, it shall bring the matter before the Commission.

The Commission shall deliver a reasoned opinion after each of the States concerned has been given the opportunity to submit its own case and its observations on the other party’s case both orally and in writing.

If the Commission has not delivered an opinion within three months of the date on which the matter was brought before it, the absence of such opinion shall not prevent the matter from being brought before the Court.’

3

Article 260 TFEU provides:

‘(1)   If the Court of Justice of the European Union finds that a Member State has failed to fulfil an obligation under the Treaties, the State shall be required to take the necessary measures to comply with the judgment of the Court.

(2)   If the Commission considers that the Member State concerned has not taken the necessary measures to comply with the judgment of the Court, it may bring the case before the Court after giving that State the opportunity to submit its observations. It shall specify the amount of the lump sum or penalty payment to be paid by the Member State concerned which it considers appropriate in the circumstances.

If the Court finds that the Member State concerned has not complied with its judgment it may impose a lump sum or penalty payment on it.

This procedure shall be without prejudice to Article 259.

…’

4

Article 279 TFEU provides:

‘The Court of Justice of the European Union may in any cases before it prescribe any necessary interim measures.’

5

Article 36 of the Statute of the Court of Justice of the European Union provides:

‘Judgments shall state the reasons on which they are based. …’

6

The fourth paragraph of Article 39 of the Statute of the Court of Justice of the European Union provides:

‘The ruling of the President or of the Judge replacing him shall be provisional and shall in no way prejudice the decision of the Court on the substance of the case.’

7

Article 147 of the Rules of Procedure of the Court of Justice, headed ‘Amicable settlement’, provides in paragraph 1 thereof:

‘If, before the Court has given its decision, the parties reach a settlement of their dispute and inform the Court of the abandonment of their claims, the President shall order the case to be removed from the register and shall give a decision as to costs in accordance with Article 141, having regard to any proposals made by the parties on the matter.’

8

Article 160 of those rules, headed ‘Application for suspension or for interim measures’, provides:

‘1.   An application to suspend the operation of any measure adopted by an institution, made pursuant to Article 278 TFEU or Article 157 TEAEC, shall be admissible only if the applicant has challenged that measure in an action before the Court.

2.   An application for the adoption of one of the other interim measures referred to in Article 279 TFEU shall be admissible only if it is made by a party to a case before the Court and relates to that case.

3.   An application of a kind referred to in the preceding paragraphs shall state the subject matter of the proceedings, the circumstances giving rise to urgency and the pleas of fact and law establishing a prima facie case for the interim measure applied for.

…’

9

Article 162 of those rules provides:

‘1.   The decision on the application shall take the form of a reasoned order, from which no appeal shall lie. The order shall be served on the parties forthwith.

2.   The execution of the order may be made conditional on the lodging by the applicant of security, of an amount and nature to be fixed in the light of the circumstances.

3.   Unless the order fixes the date on which the interim measure is to lapse, the measure shall lapse when the judgment which closes the proceedings is delivered.

4.   The order shall have only an interim effect, and shall be without prejudice to the decision of the Court on the substance of the case.’

10

Article 163 of the Rules of Procedure provides:

‘On application by a party, the order may at any time be varied or cancelled on account of a change in circumstances.’

11

On 26 February 2021, the Czech Republic brought an action under Article 259 TFEU for a declaration that the Republic of Poland had failed to fulfil its obligations under EU law as a result of the extension and continuation of lignite mining activities at the open-cast mine in Turów (Poland), located close to the borders of the Czech Republic and the Federal Republic of Germany (Case C‑121/21).

12

At the same time, the Czech Republic brought an application for interim measures under Article 279 TFEU seeking an order that the Republic of Poland immediately cease lignite mining activities at the Turów mine, pending the judgment of the Court on the substance of the case.

13

By order of 21 May 2021, Czech Republic v Poland (C‑121/21 R, ‘the order of 21 May 2021’, EU:C:2021:420), the Vice-President of the Court granted that application and ordered the Republic of Poland to cease, immediately and pending delivery of the judgment closing the proceedings in Case C‑121/21, mining activities at that mine.

14

On 7 June 2021, the Czech Republic, taking the view that the Republic of Poland had not complied with the order of 21 May 2021, brought a fresh application for interim measures under Article 279 TFEU asking that the Republic of Poland be ordered to pay a penalty of EUR 5000000 per day to the EU budget until it complies with the order of 21 May 2021.

15

On 29 June 2021, the Republic of Poland submitted an application, pursuant to Article 163 of the Rules of Procedure, for the order of 21 May 2021 to be cancelled.

16

By order of 20 September 2021, the Vice-President of the Court, first, dismissed the Republic of Poland’s application for cancellation of the order of 21 May 2021 and, second, ordered that Member State to pay the Commission a penalty of EUR 500000 per day, from the date of notification of the order of 20 September 2021 until that Member State complies with the order of 21 May 2021.

17

On 19 October 2021, the Commission asked the Polish authorities to provide evidence that lignite mining activities at the Turów mine had ceased. The Republic of Poland failed to provide such evidence and therefore, between 5 November 2021 and 8 March 2022, the Commission sent that Member State requests for payment of the amounts owing pursuant to the daily penalty at the end of each period of 30 calendar days that had elapsed.

18

On 3 February 2022, the Czech Republic and the Republic of Poland concluded an agreement ending the dispute that gave rise to Case C‑121/21 (‘the settlement agreement’).

19

On 4 February 2022, the two Member States informed the Court that they were abandoning all claims in Case C‑121/21 following the settlement agreement and the Polish authorities asked the Commission to discontinue the procedure for enforcement of the periodic penalty payments imposed by the order of 20 September 2021.

20

By order of 4 February 2022, Czech Republic v Poland (Turów mine) (C‑121/21, ‘the order of 4 February 2022’, EU:C:2022:82), Case C‑121/21 was removed from the Court’s register.

21

On the same day, the Republic of Poland lodged an application, pursuant to Article 163 of the Rules of Procedure, for cancellation of the order of 20 September 2021.

22

On 11 February 2022, the Polish authorities again requested the Commission to discontinue the procedure for enforcement of the periodic penalty payments imposed by the Court in that order.

23

On 22 February 2022, the Commission replied to the Republic of Poland’s letters of 4 and 11 February 2022, stating that, as long as the order of 20 September 2021 had not been ‘set aside’, it intended to continue to recover the amounts payable up to 3 February 2022.

24

By order of 19 May 2022, Czech Republic v Poland (Turów mine) (C‑121/21 R-RAP, ‘the order of 19 May 2022’, EU:C:2022:408), the Vice-President of the Court dismissed the Republic of Poland’s application for cancellation of the order of 20 September 2021. Paragraph 26 of that order reads as follows: ‘consequently, in the present case, as from 4 February 2022, the date of the order of the President of the Court of Justice, Czech Republic v Poland (Turów mine) (C‑121/21, … EU:C:2022:82), ordering the removal of Case C‑121/21 from the register of the Court of Justice, the Republic of Poland is no longer required immediately to cease lignite mining activities at the Turów mine. Similarly, the order requiring that Member State to pay the Commission a penalty of EUR 500000 per day until those activities cease must be regarded as having lapsed as from that date.’

25

After issuing the Republic of Poland with formal notice to pay the amounts due up to 3 February 2022 together with default interest and stating that, if payment was not made, it would recover those amounts by way of set-off, in accordance with Article 101(1) and Article 102 of Regulation (EU, Euratom) 2018/1046 of the European Parliament and of the Council of 18 July 2018 on the financial rules applicable to the general budget of the Union, amending Regulations (EU) No 1296/2013, (EU) No 1301/2013, (EU) No 1303/2013, (EU) No 1304/2013, (EU) No 1309/2013, (EU) No 1316/2013, (EU) No 223/2014, (EU) No 283/2014, and Decision 541/2014/EU and repealing Regulation (EU, Euratom) No 966/2012 (OJ 2018 L 193, p. 1; ‘the Financial Regulation’), the Commission decided to set off the amounts due under the periodic penalty payment imposed by the Court in the order of 20 September 2021. By its decisions of 7 and 8 February 2022 and of 16 and 31 March 2022, it set off the amounts payable for the period between 20 September 2021 and 17 January 2022 and, by its decision of 16 May 2022, it set off the amounts payable for the period from 18 January 2022 to 3 February 2022 inclusive. The principal amount thus recovered by way of set-off amounted to approximately EUR 68500000.

26

By applications lodged at the Registry of the General Court on 19 April and 25 May 2022, respectively, the Republic of Poland brought two actions under Article 263 TFEU seeking the annulment, first, of the decisions of 7 and 8 February 2022 and 16 and 31 March 2022 and, second, of the decision of 16 May 2022.

27

In support of its actions for annulment, the Republic of Poland raised two identical pleas in law, alleging, first, infringement of Article 101(1) and Article 102 of the Financial Regulation, read in conjunction with Article 98 of that regulation, and, second, infringement of Article 296 TFEU and of Article 41(2)(c) and Article 47 of the Charter of Fundamental Rights of the European Union.

28

In the judgment under appeal, the General Court rejected those two pleas as unfounded and, consequently, dismissed the actions in their entirety.

29

As regards, more specifically, the consequences of removing Case C‑121/21 from the register on the daily penalty payment imposed on the Republic of Poland, the General Court, in paragraph 40 of the judgment under appeal noted, in essence, first of all, that the order of 4 February 2022 made no mention of the interim measures prescribed by the order of 21 May 2021 or of the daily penalty payment imposed under Article 279 TFEU, next, that the Republic of Poland’s application for cancellation of the order of 20 September 2021 had been dismissed in the order of 19 May 2022 and, lastly, that it was expressly stated in paragraph 26 of that order that the order requiring the Republic of Poland to pay the Commission a penalty of EUR 500000 per day until the lignite mining activities at the Turów mine cease was to be regarded as having lapsed as from 4 February 2022, with the result that that periodic penalty payment had ceased to have effect from that date.

30

In paragraph 41 of the judgment under appeal, the General Court found that that periodic penalty was payable during the period between the date of service of the order of 20 September 2021 and the date of the removal of Case C‑121/21 from the register of the Court of Justice and, in paragraph 42 of that judgment, it held, in essence, that although removing that case from the register had had an impact on the period during which the periodic penalty was payable, it did not, by contrast, have the effect of extinguishing the Republic of Poland’s obligation to settle the amount owing pursuant to that periodic penalty payment, and any other conclusion would be to deviate from the purpose of the daily penalty payment, which is to guarantee the effective application of EU law, such application being an essential component of the rule of law, a value enshrined in Article 2 TEU.

31

The General Court found that the arguments put forward by the Republic of Poland were not capable of calling that conclusion into question.

32

In the first place, it pointed out, in paragraph 44 of the judgment under appeal, that the order of 20 September 2021 was not open to appeal and could not therefore be set aside retroactively.

33

In the second place, it considered, in response to the Republic of Poland’s argument that most national legal systems provide that provisional measures ordered cease retroactively to produce their effects when the main proceedings become devoid of purpose, that referring to national procedural rules is irrelevant, since, in the present case, the legality of the decisions at issue had to be examined solely in the light of the rules of EU law. In that regard, the General Court pointed out, in paragraph 45 of the judgment under appeal, that that Member State had acknowledged that the procedural rules of the Member States were not binding on the Courts of the European Union and, in paragraph 46 of that judgment, that, even if, in certain national legal systems, provisional measures ordered, pending a final decision, retroactively cease to produce their effects when the main proceedings become devoid of purpose, that finding cannot suffice to establish that those procedural rules form part of the constitutional traditions common to the Member States and could, on that basis, form part of the legal order of the European Union as a source of law.

34

In the third place, the General Court rejected, in paragraph 47 of the judgment under appeal, the argument that continuing to enforce the daily penalty payment, despite the removal of Case C‑121/21 from the register, would go beyond the sole objective pursued by that periodic penalty payment, namely to guarantee the effectiveness of the judgment on the substance of the case. In that regard, it found that, in the present case, the daily penalty payment imposed under Article 279 TFEU was intended not only to guarantee the effectiveness of the judgment on the substance of the case, but also to ensure compliance with the interim measures prescribed by the order of 21 May 2021 and to deter the Republic of Poland from delaying compliance with that order. In paragraph 48 of the judgment under appeal, the General Court added, in essence, that the Republic of Poland’s line of argument could not be upheld since the periodic penalty payment mechanism imposed under Article 279 TFEU would be deprived of all substance, in that it would be tantamount to accepting that the party liable to make payment was deliberately failing to fulfil the obligation to comply with the interim measures ordered until the close of the main proceedings, thereby undermining the effectiveness of EU law.

35

Since the two other arguments put forward by the Republic of Poland with regard to the consequences of removing Case C‑121/21 from the register were also rejected by the General Court, the General Court held, in paragraph 51 of the judgment under appeal, that there had been no infringement by the Commission of Articles 101 and 102 of the Financial Regulation, read in conjunction with Article 98 of that regulation.

36

By its appeal, the Republic of Poland claims that the Court should:

37

The Commission contends that the Court should:

38

In support of its appeal, the Republic of Poland puts forward two grounds of appeal, alleging, first, infringement of Article 279 TFEU and, second, infringement of Article 36 of the Statute of the Court of Justice of the European Union.

39

The first ground of appeal relied on by the Republic of Poland is divided into four parts. Since the arguments put forward in support of the first to third parts overlap, it is appropriate to examine those parts together.

40

By the first part of its first ground of appeal, the Republic of Poland claims that the General Court misinterpreted the principle that proceedings for interim measures are provisional and ancillary in relation to the main proceedings and that it gave precedence to the principle of effectiveness of EU law over the principle of the protection of the interests of the party seeking interim measures. The approach adopted in paragraphs 42 and 47 of the judgment under appeal is tantamount to conferring an autonomous character on interim measures consisting in an order to pay a daily penalty in that those measures serve different interests from those pursued by ‘ordinary’ interim measures. However, Article 279 TFEU does not permit the adoption of interim measures of such an autonomous nature. The only objective that can be pursued by an interim measure consisting in the imposition of a daily penalty payment is, in view of its nature, that stemming from Article 279 TFEU, namely to ensure the effectiveness of the final judgment to be given on the substance of the case. An interim measure consisting in the imposition of such a periodic penalty payment is also subject to the objective of protecting the interests of the party seeking that interim measure.

41

It is true that, in paragraph 47 of the judgment under appeal, the General Court held that the objective pursued by the periodic penalty payment, namely to ensure compliance with the interim measures, must be placed on an equal footing with the objective of guaranteeing the effectiveness of the final judgment. However, the conclusion reached by the General Court at the end of its reasoning produces a different outcome as it gave precedence to the first of those objectives over the second. According to the Republic of Poland, once an order imposing ‘principal’ interim measures becomes devoid of purpose because of the removal from the register of the case to which the interim proceedings relate, the ‘ancillary’ interim measure, in the present case the imposition of a daily penalty payment, also becomes devoid of purpose. Thus, the disappearance of the reason for which the interim measures were ordered removes any justification for pursuing their enforcement.

42

The principle of the effectiveness of EU law, which, having regard to the judgment under appeal, applies to the order of 20 September 2021, that is to say, a secondary element in relation to the order of 21 May 2021 which ordered the principal interim measures, consisting in the immediate cessation of lignite mining activities at the Turów mine, cannot prevail over the general principle on which measures adopted under Article 279 TFEU are based, namely the principle that those measures are provisional and ancillary in relation to the resolution of the case on the merits. In paragraph 42 of the judgment under appeal, the General Court failed to have regard to the primary function of interim measures, which is based on the principle that proceedings for interim measures are ancillary and provisional in relation to the proceedings on the substance of the case.

43

By the second part of its first ground of appeal, the Republic of Poland claims that the General Court failed to observe the principle that measures ordered under Article 279 TFEU are provisional and ancillary by adopting an interpretation which prevents a party to the proceedings from having its proprietary rights re-established at the end of the proceedings on the substance of the case.

44

In that regard, the Republic of Poland submits, first, that it is settled case-law that, save in exceptional circumstances, damage of a pecuniary nature cannot be regarded as irreparable or even as being reparable only with difficulty, since financial compensation for that damage can normally be obtained subsequently. It is for the judge hearing the application for interim measures to determine whether the proprietary rights of the party concerned may be re-established at the end of the proceedings on the substance of the case and execution of the order imposing interim measures can, in accordance with Article 162(2) of the Rules of Procedure, be made conditional on the lodging by the applicant of security. That possibility serves to ensure that the defendant is able to have its proprietary rights re-established if it is successful in the proceedings on the substance of the case. However, the approach adopted by the General Court in the judgment under appeal is tantamount to attributing an irreversible nature to the daily penalty payment imposed.

45

The Republic of Poland argues, second, that there is no basis in Article 279 TFEU for the finding in paragraph 42 of the judgment under appeal that the removal of the case on the merits from the register does not have the effect of bringing to an end, with ex tunc effect, the interim measures consisting in the obligation to pay a periodic penalty. The continued enforcement of that obligation neutralises the effects of the discontinuance of the proceedings following the removal of the case on the merits from the Court’s register. The interpretation adopted by the General Court in the judgment under appeal does not remedy the effects produced by the interim measures and perpetuates their negative effects for the party liable to make payment, irrespective of the outcome of the case on the merits. The consequence of such an interpretation is that any debts arising from the obligation to pay the daily penalty at issue in the present case cannot be the subject of any restitution measure, in particular an action for damages.

46

By the third part of its first ground of appeal, directed against paragraphs 47 and 48 of the judgment under appeal, the Republic of Poland contends that the General Court adopted an interpretation of Article 279 TFEU which transforms an interim measure in the form of an obligation to pay a daily penalty into an autonomous measure of a punitive nature. However, Article 279 TFEU does not confer on the judge hearing an application for interim measures the power to impose sanctions. Since enforcing an obligation arising from an order for interim measures that has become devoid of purpose can clearly no longer serve a preventive purpose, such enforcement clearly serves a punitive purpose consisting in penalising the party liable to make payment for having failed to comply with that obligation.

47

Moreover, the objective of guaranteeing the effective application of EU law, such application being an essential component of the rule of law, a value enshrined in Article 2 TEU, referred to in paragraphs 32 and 42 of the judgment under appeal, cannot justify the interpretation of Article 279 TFEU adopted by the General Court since that objective can be effectively achieved through infringement proceedings brought under Article 258 TFEU and enforced by means of the penalties provided for in Article 260(2) TFEU.

48

The Commission contends that those three parts of the first ground of appeal are unfounded and should therefore be rejected.

49

It should be borne in mind that the purpose of seeking to ensure that a Member State complies with interim measures adopted by the judge hearing an application for such measures by providing for the imposition of a periodic penalty payment in the event of non-compliance with those measures is to guarantee the effective application of EU law, such application being an essential component of the rule of law, a value enshrined in Article 2 TEU and on which the European Union is founded (order of 20 November 2017, Commission v Poland, C‑441/17 R, EU:C:2017:877, paragraph 102).

50

While it is true that the scope of proceedings for interim measures under Article 279 TFEU is limited by their ancillary nature vis-à-vis the main action and by the provisional nature of the measures that may be adopted in those proceedings, a feature of that scope is nonetheless the breadth of the powers which are afforded to the judge hearing an application for interim measures in order to enable that judge to guarantee the full effectiveness of the final decision (order of 20 November 2017, Commission v Poland, C‑441/17 R, EU:C:2017:877, paragraph 103).

51

Accordingly, if the judge hearing an application for interim measures considers that the circumstances of the case require additional measures to be taken in order to ensure the effectiveness of the measures requested, he or she has power under Article 279 TFEU, inter alia, to prescribe the imposition of a periodic penalty payment on a Member State in the event that that Member State fails to comply with the interim measures ordered (order of 20 November 2017, Commission v Poland, C‑441/17 R, EU:C:2017:877, paragraph 104).

52

Since the prospect of a periodic penalty payment being imposed in such a situation encourages the relevant Member State to comply with the interim measures ordered, it enhances the effectiveness of those measures and guarantees the full effectiveness of the final decision, thus falling entirely within the ambit of the objective of Article 279 TFEU (order of 20 November 2017, Commission v Poland, C‑441/17 R, EU:C:2017:877, paragraph 105).

53

It is apparent from the case-law referred to in paragraphs 49 to 52 above that the imposition, by the judge hearing an application for interim measures, of a daily penalty payment in the event of non-compliance by a Member State with a principal interim measure imposed on it must be regarded as an ancillary interim measure intended to guarantee the full effectiveness, first, of the order imposing that principal interim measure and, second, of the final decision to be taken and, therefore, the effective application of EU law.

54

As regards the Republic of Poland’s argument that, in proceedings for interim measures, the principle of effectiveness of EU law must be given the same weight as the principle of protection of the interests of the party seeking interim measures, it is true that, in accordance with Article 160(3) of the Rules of Procedure, it is for the applicant to request the interim measures that it considers necessary and to establish that the conditions for granting them are satisfied. However, the fact remains that, in a case such as that giving rise to the present dispute, the daily penalty is not paid to the party which requested that it be imposed and is not intended to compensate that party for the failure by the other party to comply with the principal interim measures ordered by the judge hearing the application for interim measures under Article 279 TFEU. That periodic penalty is paid to the EU budget, which proves that it is intended to guarantee the effective application of EU law in the general interest.

55

Moreover, once the matter is before it, the Court hearing the application for interim measures must satisfy itself that the measures that it is minded to order are sufficiently effective to achieve their aim and adopt, within the exercise of the broad discretion conferred on it by Article 279 TFEU, where necessary of its own motion, any ancillary measure intended to guarantee the effectiveness of the interim measures that it orders (see, to that effect, order of 20 November 2017, Commission v Poland, C‑441/17 R, EU:C:2017:877, paragraphs 98 and 99). Therefore, once the judge hearing the application for interim measures has adopted a decision imposing an interim measure, whether principal or ancillary, the party requesting that interim measure is no longer able to amend its application in respect of the past, but only in respect of the future.

56

An interpretation according to which the parties to the dispute may bring proceedings in respect of an interim measure sought and ordered under Article 279 TFEU only in respect of the future and not in respect of the past is supported by both Article 163 and Article 162 of the Rules of Procedure.

57

As regards Article 163 of the Rules of Procedure, it should be borne in mind that, in accordance with the Court’s case-law, an application made under that provision seeks to obtain from the judge hearing an application for interim measures not the retroactive setting aside of an order granting an interim measure, but only its variation or cancellation, since the judge hearing an application for interim measures may reconsider such an order only in respect of the future, including, where appropriate, by reassessing, in the light of the circumstances existing at the date of his or her decision, the pleas of fact and law which established a prima facie case for the grant of the interim measure at issue (order of 19 May 2022, paragraph 22 and the case-law cited). While the judge hearing an application for interim measures may reconsider such an order only in respect of the future, it is clear that the actions of the parties to the dispute, including the conclusion of a settlement agreement, cannot have the effect of retroactively varying, annulling or setting aside an order imposing such interim measures or its effects.

58

As regards Article 162 of the Rules of Procedure, it is clear that that provision, in so far as it provides that ‘no appeal shall lie’ from orders imposing interim measures, likewise leaves no room for any retroactive variation, annulment or setting aside of interim measures ordered by the judge hearing the application for interim measures.

59

The foregoing interpretation is, moreover, supported by the Court’s case-law, from which it follows that, notwithstanding the fact that a daily penalty payment imposed as an ancillary interim measure with the sole aim of ensuring compliance with the principal interim measures is of an irreversible nature, the imposition of such a periodic penalty payment in no way prejudges the decision on the substance of the case and therefore comes within the scope of Article 279 TFEU (see, to that effect, order of 20 November 2017, Commission v Poland, C‑441/17 R, EU:C:2017:877, paragraphs 106 to 108).

60

If the imposition of such a periodic penalty payment by the judge hearing the application for interim measures may be regarded as not prejudging the decision on the substance of the case, that is because that ancillary interim measure, namely the daily penalty payment in question, is imposed, first, to ensure compliance with the interim measures at issue and, second, to preserve the full effectiveness of the future final decision and thus to guarantee the effective application of EU law, such application being an essential component of the rule of law, a value enshrined in Article 2 TEU and on which the European Union is founded.

61

Moreover, the interpretation set out in paragraph 54 above is not invalidated by the argument that interim measures are merely ancillary vis-à-vis the proceedings on the substance of the case. As is apparent from paragraphs 51 and 52 above, the Court, while recognising that the scope of proceedings for interim measures under Article 279 TFEU is limited by the fact that they are ancillary to the proceedings on the substance of the case and by the provisional nature of the measures that may be adopted at the end of the proceedings for interim relief, has nevertheless held that the judge hearing an application for interim measures has the power, under Article 279 TFEU, to order that a periodic penalty payment be imposed on a Member State in the event that that Member State fails to comply with the interim measures ordered. The fact that interim measures are ancillary to the proceedings on the substance of the case does not prevent some of those measures from producing, despite their application over a specified period, irreversible effects during that period in that, in accordance with Article 162 of the Rules of Procedure and without prejudice to Article 163 of those rules, they produce those effects until the date fixed in the order imposing them or until delivery of the judgment closing the proceedings.

62

As regards the Republic of Poland’s argument that, following the settlement agreement concluded with the Czech Republic, the order of 21 May 2021 imposing the principal interim measures became devoid of purpose so that there is no longer any need to ensure their effectiveness by means of a daily penalty payment and that the order of 20 September 2021 imposing that periodic penalty payment has therefore also become devoid of purpose, suffice it to note that, as follows from the above considerations, the effects of an ancillary interim measure can be lifted only for the future and cannot be annulled or varied retroactively.

63

It should be added that the Court has also held that the imposition, by the judge hearing the application for interim measures, of a periodic penalty payment with the aim of ensuring compliance with the interim measures in no way prejudges the future decision on the substance of the case, with the result that an ancillary measure consisting in the imposition of a daily penalty payment in the event that a Member State fails to comply with the interim measures imposed on it comes within the scope of Article 279 TFEU (see, to that effect, order of 20 November 2017, Commission v Poland, C‑441/17 R, EU:C:2017:877, paragraphs 107 and 108).

64

Contrary to the Republic of Poland’s contention, maintaining, despite the settlement agreement, the obligation to pay the amount owing pursuant to the daily penalty payment imposed in the order of 20 September 2021 does not undermine the purpose of that periodic penalty payment, namely to guarantee the effective application of EU law. In the present case, it is common ground that, until the conclusion of the settlement agreement, the Republic of Poland had not complied with either the principal interim measures imposed in the order of 21 May 2021 or the ancillary interim measure imposed in the order of 20 September 2021, with the result that that purpose had not been achieved.

65

As regards the Republic of Poland’s argument that the approach adopted by the General Court in paragraphs 47 and 48 of the judgment under appeal amounts to conferring a punitive character on the daily penalty payment, whereas, in accordance with Article 279 TFEU, the judge hearing the application for interim measures does not have the power to impose sanctions, it should be recalled that the Court of Justice has previously held that a daily penalty payment imposed in order to ensure the effectiveness of an order directed at a party under Article 279 TFEU cannot be seen as a punishment (order of 20 November 2017, Commission v Poland, C‑441/17 R, EU:C:2017:877, paragraph 102).

66

Since a daily penalty payment imposed by the judge hearing the application for interim measures in order to guarantee the effective application of an order imposing principal interim measures enhances the effectiveness of those measures by encouraging the Member State concerned to bring to an end its failure to comply with its obligations under that order, that daily penalty payment guarantees, from the time it is imposed, the full effectiveness of the final decision to be taken and the effective application of EU law, such application being an essential component of the rule of law, a value enshrined in Article 2 TEU and on which the European Union is founded, and thus unquestionably comes within the ambit of the objective of Article 279 TFEU (see, to that effect, order of 20 November 2017, Commission v Poland, C‑441/17 R, EU:C:2017:877, paragraph 105, and judgment of 18 December 2025, Commission v Poland (Ultra vires review of the Court’s case-law – Primacy of EU law), C‑448/23, EU:C:2025:975, paragraph 130). Such a daily penalty payment is therefore preventive and not punitive in nature.

67

The mere fact that, as in the present case, the Member State concerned has not complied with either the order imposing the principal interim measures or the order imposing the ancillary interim measure, namely the payment of a daily penalty, prior to the close of the case on the merits is not capable of altering the preventive nature of the daily penalty payment imposed by the judge hearing the application for interim measures pursuant to Article 279 TFEU. Any other interpretation would undermine the effectiveness of such an ancillary interim measure by allowing the party liable to make payment to rely on its own failure to act in order to challenge the legality of the measure adopted.

68

In the light of the foregoing, it must be held that, by holding in paragraph 47 of the judgment under appeal that, in the present case, the daily penalty payment imposed under Article 279 TFEU was intended not only to guarantee the effectiveness of the judgment on the substance of the case, but also to ensure compliance with the interim measures prescribed by the order of 21 May 2021 and to deter the Republic of Poland from delaying compliance with that order, and, in paragraph 48 of that judgment, that the Republic of Poland’s line of argument could not be upheld since it would deprive the periodic penalty payment mechanism imposed under Article 279 TFEU of all substance, the General Court adopted an interpretation of that article which is consistent with the case-law of the Court of Justice and free from any error of law.

69

As regards the Republic of Poland’s argument that the General Court adopted an interpretation of Article 279 TFEU which would prevent the defendant from having its proprietary rights re-established at the end of the proceedings on the substance of the case, it is common ground that, after the removal of the case on the merits from the register following the settlement agreement concluded between the Czech Republic and the Republic of Poland, the latter could not have been successful in those proceedings.

70

Lastly, as regards the Republic of Poland’s argument that the objective of ensuring the effective application of EU law could be effectively pursued in the context of infringement proceedings brought under Article 258 TFEU and enforced by means of the penalties provided for in Article 260(2) TFEU, it must be borne in mind that the Court has held that such an interpretation of the system of legal remedies under EU law in general and of proceedings for interim measures in particular would undermine the objective of those proceedings, which is to ensure compliance by the Member State concerned with the interim measures imposed on it and the effective application of EU law, such application being an essential component of the rule of law, a value enshrined in Article 2 TEU and on which the European Union is founded (see, to that effect, order of 20 November 2017, Commission v Poland, C‑441/17 R, EU:C:2017:877, paragraph 102).

71

It follows that, in holding, in paragraphs 32, 42 and 48 of the judgment under appeal, that to follow the approach advocated by the Republic of Poland – according to which, in the present case, the removal of the case on the merits from the register had the effect of extinguishing its obligation to settle the amount payable in respect of the daily penalty payment imposed in the order of 20 September 2021 – would be to deviate from the purpose of that periodic penalty payment, which is to guarantee the effective application of EU law, such application being an essential component of the rule of law, a value enshrined in Article 2 TEU, the General Court adopted an interpretation of Article 279 TFEU which is consistent with the case-law of the Court of Justice and did not err in law.

72

The first to third parts of the first ground of appeal must therefore be rejected as unfounded.

73

By the fourth part of its first ground of appeal, directed against paragraphs 40 and 42 of the judgment under appeal, the Republic of Poland complains that the General Court erred in its interpretation of the order of 19 May 2022 by considering, on the basis of that order, that the removal of the case on the merits from the register did not have the effect of extinguishing the Republic of Poland’s obligation to pay the amount owing pursuant to the periodic penalty. According to the Republic of Poland, the order of 19 May 2022 did not address the retroactive effects of the cessation of the interim measures and was irrelevant to the determination of the effects that removing the case on the merits from the register in Case C‑121/21 had on the obligation imposed on the Republic of Poland to pay the amount owing pursuant to the daily penalty for the period prior to the date on which that case was removed from the Court’s register. The Republic of Poland therefore argues that the General Court was not entitled to draw any inference from the order of 19 May 2022 enabling it to assess that issue.

74

The Commission contends that that part of the first ground of appeal should be rejected.

75

As regards the fourth part of the first ground of appeal, it should be noted that, as the Republic of Poland was correct to state, the General Court, in paragraph 40 of the judgment under appeal, expressly referred to paragraph 26 of the order of 19 May 2022 and concluded that the daily penalty payment imposed in the order of 20 September 2021‘[had] ceased to produce its effects from 4 February 2022’. However, in the same paragraph of that judgment, the General Court also found, first, that the order of 4 February 2022 made no mention of the interim measures prescribed by the order of 21 May 2021 or of the daily penalty payment imposed under Article 279 TFEU and, second, that the Republic of Poland’s application for cancellation of the order of 20 September 2021 had been dismissed in the order of 19 May 2022.

76

As is apparent from the use of the word ‘accordingly’ at the beginning of paragraph 41 of the judgment under appeal, the General Court, on the basis of the three findings set out in paragraph 40 of that judgment and recalled in the preceding paragraph of the present judgment, held that ‘the daily penalty payment [had been] payable during the period between the date of service of the order of 20 September 2021 … and the date of removal of Case C‑121/21 from the register’.

77

In so far as paragraph 41 of the judgment under appeal, and therefore the interim assessment contained in that paragraph, is not challenged by the Republic of Poland, it must be held that the findings contained in paragraphs 40 and 41 of that judgment are sufficient to substantiate the assessment made by the General Court in paragraph 42 of that judgment, according to which the removal of the case on the merits from the register did not have the effect of extinguishing the Republic of Poland’s obligation to settle the amount payable in respect of the periodic penalty payment at issue, that assessment being based only in part on paragraph 26 of the order of 19 May 2022, which, moreover, the General Court merely reproduced verbatim in paragraph 40 of the judgment under appeal.

78

In the light of the foregoing, it must be held that the arguments relied on by the Republic of Poland in support of the fourth part of the first ground of appeal are based on a misreading of paragraphs 40 and 42 of the judgment under appeal.

79

Accordingly, the fourth part of the first ground of appeal must be rejected as unfounded.

80

In the light of the foregoing considerations, the first ground of appeal must be rejected as unfounded.

81

By its second ground of appeal, directed, in essence, against paragraph 46 of the judgment under appeal, the Republic of Poland complains that the General Court failed to comply with its obligation to state reasons by failing properly to state the reasons why it rejected the argument that national procedural rules providing that interim measures ordered, pending a final decision, retroactively cease to produce their effects when the proceedings on the substance become devoid of purpose form part of the constitutional traditions common to the Member States and can, on that basis, form part of the legal order of the European Union as a source of law.

82

After rejecting, in paragraph 45 of the judgment under appeal, the Republic of Poland’s line of argument on the ground that the legality of the decisions at issue had to be examined solely in the light of the rules of EU law, the General Court, in paragraph 46 of that judgment, made a mere assertion in order to reject the argument that the national provisions relied on by the Republic of Poland could be regarded as forming part of the legal order of the European Union as a source of law within the meaning of Article 6(3) TEU, without identifying any provision of the Treaties or general principle of EU law that would preclude such a classification. According to the Republic of Poland, that assertion does not enable it to ascertain the reasons for the General Court’s decision.

83

The Commission contends that that ground of appeal should be rejected.

84

The second ground of appeal put forward alleges a failure to state reasons in paragraph 46 of the judgment under appeal.

85

In that regard, it should be borne in mind that, in accordance with the Court’s settled case-law, the statement of the reasons on which a judgment is based must clearly and unequivocally disclose the General Court’s reasoning, so that the persons concerned can be apprised of the justification for the decision taken and the Court of Justice can exercise its power of review (judgment of 23 January 2025, Parliament v Axa Assurances Luxembourg and Others, C‑766/21 P, EU:C:2025:31, paragraph 80 and the case-law cited).

86

In paragraph 46 of the judgment under appeal, the General Court held that ‘even if in certain national legal systems provisional measures ordered, pending a final decision, retroactively cease to produce their effects when the main proceedings become devoid of purpose, that finding cannot suffice to establish that those procedural rules form part of the constitutional traditions common to the Member States and could, on that basis, form part of the legal order of the European Union as a source of law’.

87

It is unequivocally clear from that statement of reasons that the General Court considered that, in accordance with the applicable evidentiary requirements, the procedural rules relied on by the Republic of Poland in support of its line of argument could not be regarded as forming part of the constitutional traditions common to the Member States. It follows that, as regards paragraph 46 of the judgment under appeal, that judgment is not vitiated by a failure to state reasons or by an inadequate statement of reasons.

88

It follows that the second ground of appeal must be rejected as unfounded.

89

The appeal must therefore be dismissed in its entirety.

90

Under Article 184(2) of the Rules of Procedure, where the appeal is unfounded, the Court is to make a decision as to costs.

91

Under Article 138(1) of the Rules of Procedure, which applies to appeal proceedings by virtue of Article 184(1) thereof, the unsuccessful party is to be ordered to pay the costs if they have been applied for in the successful party’s pleadings.

92

Since the Commission has applied for costs and the Republic of Poland has been unsuccessful, the latter must be ordered to bear its own costs and to pay those incurred by the Commission.

On those grounds, the Court (First Chamber) hereby: