The European Court of Justice will next month consider whether Britain can unilaterally withdraw its Article 50 Brexit letter.
It comes after Scotland’s highest court announced it would refer the question on to Luxembourg.
Due to the “urgency of the issue” – the UK will leave the European Union on March 29 – the Court of Session in Edinburgh requested the case be expedited.
The ECJ confirmed on Friday that it has “granted the fast-track procedure on the request for a preliminary ruling from a Scottish court on the reversibility of Article 50”.
Jolyon Maugham QC, who is one of the people who brought the case, said a hearing would now take place on November 27.
Appealing to the public for help with funding the legal challenge, Mr Maugham, director of the Good Law Project, said: “This is a case vital in our national interest. Please help us engage the best possible team.”
The case has been brought by Mr Maugham and a cross-party group of politicians in Scotland, comprising Labour MEPs Catherine Stihler and David Martin, Joanna Cherry MP and Alyn Smith MEP of the SNP, and Green MSPs Andy Wightman and Ross Greer.