ABSTRACT – In Commission v. United Kingdom , the ECJ found the UK to be in breach of its obligations under EU law, to which it was bound during the post–Brexit transition period. The judgment is part of the Micula saga and concerns two main issues: the possibility of applying the clause of Article 351, para. 1, TFEU to the obligation to enforce ISDS arbitral awards under Article 54 of the ICSID Convention; and the identification of the competent court to decide on the issue. The infringement proceeding concerned a judgment issued by the UK Supreme Court, in which the latter disapplied EU law under the above-mentioned clause and gave precedence to its international obligations under the ICSID Convention. However, according to the ECJ, the Supreme Court interpreted the scope of Art. 351, para. 1, TFEU too broadly, whereas it should have referred the matter to the ECJ for a preliminary ruling. As the present contribution aims to show, the case outcome reflects a situation of incommunicability between the courts involved. Although both judgments revolve around the question of the application of Art. 351, para. 1, TFEU, the two courts came to opposite conclusions, as they adopted divergent approaches. The approach of the Supreme Court rests on considerations of international law, as well as on its own role as a national court. That of the CJEU, on the other hand, consists of an assessment grounded on EU law, without replying to the merit of the Supreme Court’s arguments. In conclusion, a reflection is made on how the absence of dialogue between the courts, in the context of legal orders’ fragmentation, implies that both courts are right, at least from their own point of view.
