1.

Is Article 6 of the directive to be interpreted as meaning that the sum of EUR 40 applies per invoice in all circumstances, provided that the creditor has individually identified the invoices in his claims before the administrative authorities and the administrative courts, or does the sum of EUR 40 apply per invoice in all circumstances, even if joint and general claims have been lodged?

2.

How must Article 198(4) of Law 9/2017 [which lays down] a payment period of 60 days in all circumstances and for all contracts, providing for an initial period of 30 days for approval and another, additional period of 30 days for payment, be interpreted, in so far as [recital] 23 of the directive is worded as follows:

‘Long payment periods and late payment by public authorities for goods and services lead to unjustified costs for undertakings. It is therefore appropriate to introduce specific rules as regards commercial transactions for the supply of goods or services by undertakings to public authorities, which should provide in particular for payment periods normally not exceeding 30 calendar days, unless otherwise expressly agreed … and provided it is objectively justified in the light of the particular nature or features of the contract, and in any event not exceeding 60 calendar days.’[?]

3.

How is Article 2 of the directive to be interpreted? Does the interpretation of the directive support the conclusion that the basis for calculating late-payment interest recognised in the directive includes the VAT due on the service provided, the amount of which is included in the invoice? Or is it necessary to identify and determine the time when the contractor paid the tax to the tax administrative authority?