The CJEU has been considering whether or not Article 50 (provision of the Lisbon Treaty) can be revoked by a Member State without requiring the formal agreement of the other EU Member States or the European Commission. This was brought up at the request of a group of petitioners including various MPs, MSPs and MEPs along with a Scottish court, the Court of Session, Inner House and First Division (UK).

On 4 December 2018, The Court of Justice of the European Union (CJEU) issued the Press Release No 187/18 about the legal opinion drafted by Advocate General Campos Sánchez-Bordona where he argued that the UK can unilaterally cancel its withdrawal from the EU.

The legal opinion proposed that the UK should be able to revoke its request for withdrawal from the EU at any time during the negotiation period, provided that it is done in good faith:

"In answer to the question from the Scottish court, the Advocate General proposes that the Court of Justice should, in its future judgment, declare that Article 50 TEU allows the unilateral revocation of the notification of the intention to withdraw from the EU, until such time as the withdrawal agreement is formally concluded, provided that the revocation has been decided upon in accordance with the Member State's constitutional requirements, is formally notified to the European Council and does not involve an abusive practice."

While the Advocate General's decisions are non-binding on the CJEU, it is evident from past cases that the court tends to follow them in the majority of its final rulings.

With countdown days are plummeting towards the Brexit day on 29 March 2019, the court is expected to determine an emergency ruling within weeks but probably not until after the new year. If the court decides to endorse the AG's legal opinion, the case will be referred back to the court of session in Edinburgh for a final judgment.

Find the Press Release No 187/18 for the detailed opinion by the AG on the link below: https://curia.europa.eu/jcms/upload/docs/application/pdf/2018-12/cp180187en.pdf