Brexit hits speed bump as court rules lawmakers must get say

LONDON -- Britain's plans to leave the European Union hit a large speed bump Thursday as the High Court ruled the government can't start exit negotiations without a vote in Parliament.

The judgment deepened Britain's divide over Europe, raising hopes among pro-EU politicians they can soften the terms of the U.K.'s withdrawal from the bloc. "Leave" campaigners said any attempt to do that would be a betrayal of voters' decision.

The government immediately said it would ask the Supreme Court to overturn the ruling.

The court has set aside time in early December to hear the case.

Thursday's ruling could delay government plans to start talks on Britain's EU exit, or Brexit, within weeks and opens a major constitutional battle over the balance of power between Parliament and the government.

Brexit secretary David Davis said Britain's June 23 vote to leave the EU "must be respected."

"The people want us to get on with it, and that is what we are going to do," he said.

Prime Minister Theresa May has said she will use centuries-old powers known as royal prerogative to invoke Article 50 of the EU treaty, which launches two years of exit negotiations, by the end of March.

The powers -- traditionally held by the monarch but now used by politicians -- enable decisions about international treaties and other issues to be made without a vote of Parliament.

Several claimants, including a hairdresser and a financial entrepreneur, challenged May's right to act. They argued leaving the EU will remove rights, including free movement within the bloc, and it couldn't be done without Parliament's approval.

Three senior judges agreed, ruling "the government does not have the power under the Crown's prerogative to give notice pursuant to Article 50 for the U.K. to withdraw from the European Union."

The judges backed the claimants' argument the government could not remove Britons' legal rights "unless Parliament had conferred upon the Crown authority to do so."

The ruling infuriated pro-Brexit campaigners, who see the lawsuit as an attempt to block or delay Britain's EU exit.

U.K. Independence Party leader Nigel Farage, who helped lead the campaign to leave the EU, tweeted: "I worry that a betrayal may be near at hand."

"I now fear that every attempt will be made to block or delay the triggering of Article 50," Farage said. "If this is so, they have no idea of the level of public anger they will provoke."

It's unlikely the ruling will stop Britain leaving the EU eventually.

Most lawmakers accept the voters' decision must be respected -- but they differ widely on what form Brexit should take and how close a relationship Britain should keep with the EU.

A majority of members of Parliament backed the "remain" side in the referendum but could be willing to support the start of exit talks if it's clear the government won't seek a "hard Brexit," in which Britain leaves the EU's single market.

Pro-EU legislators hope the ruling will force the government to set out its plans for exit negotiations before triggering Article 50, something May previously has ruled out.