The CJEU held that the United Kingdom of Great Britain and Northern Ireland (UK) is allowed to unilaterally revoke the notification of its intention to withdraw from the European Union (EU) as long as the revocation is submitted in writing to the European Council before the UK's withdrawal takes effect, and as long as the revocation is “unequivocal and unconditional, that is to say that the purpose of that revocation is to confirm the EU membership of the member state concerned under terms that are unchanged as regards its status as a member state, and that revocation brings the withdrawal procedure to an end” (para. 74).

Withdrawal from international adjudication is a contemporary phenomenon with wide implications. The act of treaty withdrawal is not to be seen as merely the unilateral executive exercise of the individual sovereign prerogative of a State. International law places checks upon the exercise of withdrawal, recognising that it is an act that of its nature affects the interests of other States parties, which have a collective interest in constraining withdrawal. National courts have a complementary function in restraining unilateral withdrawal in order to support the domestic constitution. The arguments advanced against international adjudication in the name of popular democracy at the national level can serve as a cloak for the exercise of executive power unrestrained by law. The submission by States to peaceful settlement of disputes through international adjudication is central, not incidental, to the successful operation of the international legal system.