Luxembourg - Can Britain reverse its decision to leave the European Union? This question was being considered by the European Union's top court in a hearing.
The issue was initially put to the Scottish courts in a petition brought by parliamentarian Andy Wightman and others, who wanted to know whether Britain has the option of backing out of Article 50 of the EU treaty, which triggered a two-year countdown to Brexit.
The Scottish court hearing the case referred the matter to the European Court of Justice (ECJ) in early October, asking whether EU law permits a member state to unilaterally revoke its Article 50 notification and what conditions would apply.
The British government had attempted, unsuccessfully, to shut the case down, arguing that the question is purely hypothetical since it has no intention of doing so.
European Court of Justice
"An answer from the Court of Justice will clarify the options open to the parliamentarians when they vote on those matters," the Scottish court argued, according to the ECJ.
The British parliament is due to vote on December 11 on the withdrawal agreement negotiated by London and Brussels, which lays out the terms of Britain's departure from the EU, as well as a joint political declaration on the future relationship.
British Prime Minister Theresa May faces an uphill battle to get the deal through parliament, where she holds a thin majority and faces cross-party opposition.
The case is being fast-tracked by the ECJ, with a view to concluding it before Britain leaves the EU on March 29, 2019. No decision is likely before the December 11 vote, however.