Brexit judgment: Article 50 needs act of parliament

Theresa May cannot trigger Article 50 starting the clock on Britain’s exit from the EU without a vote in Parliament, the Supreme Court has ruled.

The government must win the vote of MPs and peers before the end of March if it is to meet May’s deadline for triggering Article 50.

Labour, the Liberal Democrats and the SNP said they would look to make amendments, which could lead to delays.

Investment manager Gina Miller, one of the lead claimants in the Article 50 challenge, welcomed the ruling and said: “Parliament alone is sovereign.”

Campaigners argued denying Parliament a vote would be undemocratic, but the government said it already had powers to get talks under way.

The judges rejected the case put by ministers by a majority of eight to three.