The high court has ruled that Theresa May requires the approval of parliament before she can begin the formal process to the leave the European Union, in an unexpected decision that could delay Brexit.
The pound rose by 1% against the dollar after the ruling was announced. The decision shocked Theresa May's government, which has pledged to appeal the ruling to the supreme court.
Parliamentarians are more supportive of the EU than the general public, raising concerns in the government that some MPs and peers could attempt to delay or block Brexit if they are given a vote.
and here's the pound
Theresa May had previously intended to invoke Article 50 by March 2017, beginning two years of negotiations, without consulting parliament. The government argued that June's referendum, in which 52% of the public voted to leave the EU, gives it the required mandate without giving a vote to MPs.
However, a successful legal challenge brought by a group including investment fund manager Gina Miller argued that only parliament has the right to lead Britain out of the EU and there should be a full debate in parliament.
Campaign leader Gena Miller speaks after Article 50 High Court victory over government https://t.co/zJnNQFtXbk
Outside court Miller said the government should accept it is now time for "a proper debate in our sovereign parliament" about the Article 50 process.
Flipping the argument of Vote Leave campaigners on its head, she said it was about the British parliament having sovereignty over key political decisions: "You can't on the day you get back sovereignty throw it away.
"You can't have a government casually throwing away people's rights – that's why we turned to the courts."
Miller said she received racist abuse after bringing the legal challenge, which was heard by three of Britain's top judges in October.
Labour leader Jeremy Corbyn said that while his party respected the British public's decision to vote to the leave the EU, the court ruling showed the need for "transparency and accountability to parliament on the terms of Brexit".
The legal case hinged on whether the government has the right to invoke Article 50, starting the formal process of leaving the EU, without the approval of parliament.
In its ruling, the court said the government did not have power under royal prerogative to trigger Article 50 without first consulting MPs.
The government argued that the court case was an attempt to undermine the democratic will of the British people.
Following the judgment, a government spokesperson said it was "disappointed", and said it would appeal the decision.
David Davis, the government's Brexit secretary, told Sky News unless the court's decision is overturned, MPs will have to pass an act of parliament to trigger Article 50 – requiring both politicians and peers approval.
The government intended to appeal because, Davis said, the referendum was held only after MPs voted 6-1 to give the decision to the British people.
"The people are the ones parliament represents – 17.4m of them, the biggest mandate in history, voted for us to leave the European Union," he told the BBC.
Scottish first minister Nicola Sturgeon tweeted that today's High Court ruling was "significant indeed".
UKIP interim leader Nigel Farage said he was worried that "a betrayal may be near at hand".
"Last night at the Spectator Parliamentary Awards I had a distinct feeling that our political class, who were out in force, do not accept the 23 June referendum result," he said in a statement.
"I now fear that every attempt will be made to block or delay the triggering of Article 50. If this is so, they have no idea of the level of public anger they will provoke."
But pro-Remain Tory MP Anna Soubry said today's judgment was "all about the sovereignty of parliament not reopening" the EU referendum debate.
Labour MP David Lammy, who previously called for a parliamentary vote on whether Britain should leave the EU, called today's ruling a "huge victory for our parliamentary democracy".
Green party co-leader Caroline Lucas tweeted that MPs voting on Article 50 was "what taking back control should be about".
Brilliant news! Parliament to have a say before Article 50 is triggered - that’s what taking back control should be… https://t.co/MTubQ54uFO
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