However, it does not suffice that a measure is classified, by an institution featuring as the defendant in an action, as a ‘decision of the Member States’ of the European Union in order for such a measure to escape the review of legality established by Article 263 TFEU, in the present case, measures of the European Council. In order for such a measure to be excluded from review, it is still necessary to determine whether, having regard to its content and all the circumstances in which it was adopted, the measure in question is not in reality a decision of the European Council.

However, measures adopted by the representatives of the Member States physically gathered in the grounds of one of the European Union institutions and acting, not in their capacity as members of the Council or European Council, but in their capacity as Heads of State or Government of the Member States of the European Union, are not subject to judicial review by the European Union Courts. In that regard, it follows from Article 263 TFEU that, generally, the EU judicature does not have jurisdiction to rule on the lawfulness of a measure adopted by a national authority or of a measure adopted by the representatives of the national authorities of several Member States acting in the framework of a committee provided for in a European Union regulation.

The Lisbon Treaty established the European Council as an institution of the European Union. Thus, contrary to what had been found previously by the European Union Courts, the measures adopted by that institution, which, according to Article 15 TEU, does not exercise legislative functions and consists of the Heads of State or Government of the Member States, together with its President and the President of the Commission, no longer escape the review of legality provided for in Article 263 TFEU.

The statement published on the Council’s website on 18 March 2016, in the form of a press release, designed to give an account of the results of a meeting between EU heads of State or Government and the Turkish Prime Minister with a view to deepening Turkey-EU relations and addressing the migration crisis cannot be regarded as a measure open to an action under Article 263 TFEU. Such a measure cannot be regarded as a measure adopted by the European Council, or, moreover, by any other institution, body, office or agency of the European Union, or as revealing the existence of such a measure that corresponds to an agreement allegedly concluded on 18 March 2016 between the European Council and the Republic of Turkey.

To the extent that, for the purposes of the first paragraph of Article 21 of the Statute of the Court of Justice, the contested measure was given form by the production of a press release, the circumstances in which the EU-Turkey statement, as published by that press release, was adopted and the content of that statement must be examined in order to determine whether it may constitute or reveal the existence of a measure attributable to the European Council and, thus, falling under the review of legality laid down in Article 263 TFEU. Those documents, officially sent to the Member States of the European Union and the Republic of Turkey, thus establish that, notwithstanding the regrettably ambiguous terms of the EU-Turkey statement, as published by means of Press Release No 144/16, it was in their capacity as Heads of State or Government of the Member States that the representatives of those Member States met with the Turkish Prime Minister on 18 March 2016 in the premises shared by the European Council and the Council. In this regard, the fact that the President of the European Council and the President of the Commission, not formally invited, had also been present during that meeting cannot allow the conclusion that, because of the presence of all those Members of the European Council, the meeting of 18 March 2016 took place between the European Council and the Turkish Prime Minister.

Moreover, even supposing that an international agreement could have been informally concluded during the meeting of 18 March 2016, that agreement would have been an agreement concluded by the Heads of State or Government of the Member States of the European Union and the Turkish Prime Minister. In an action brought under Article 263 TFEU, the Court does not have jurisdiction to rule on the lawfulness of an international agreement concluded by the Member States.

(see paras 47, 65, 66, 70-72)