Brexit: Next stop the Supreme Court as speculation mounts Prime Minister could go to the country early
The future of Brexit now appears to rest with the Supreme Court after High Court judges dealt what could be a fatal, historic blow to Government plans to use the Royal Prerogative to start the process of exiting the EU without the authorisation of Parliament.
And MPs have suggested that Prime Minister Theresa May could call a snap general election next year to ensure she has enough supportive MPs to get her Brexit plan through the House of Commons.
Three judges unanimously ruled Mrs May did not have the power to bypass MPs by relying on the prerogative to trigger Article 50 of the Treaty on European Union and begin the two-year period of divorce negotiations with the 27 other countries in the EU bloc.
The Lord Chief Justice, Lord Thomas, said to do so would be contrary to "the fundamental constitutional principles of the sovereignty of Parliament".
The court rejected the Government argument that prerogative powers were a legitimate way to give effect "to the will of the people" who voted by a clear majority to leave the EU in June.
Lord Thomas - sitting with the Master of the Rolls, Sir Terence Etherton, and Lord Justice Sales - emphasised to a packed court in London they were deciding "a pure question of law" and not expressing any view about the "political issue" concerning the merits of leaving the EU.
The pound rose sharply after the judgment, but the Government swiftly announced it is to appeal to the highest court in the land.
It is widely expected that 11 Supreme Court justices will sit before Christmas to hear one of the most important constitutional cases in generations.
Anti-prerogative campaigners were celebrating the High Court victory in London, while the Government expressed its "disappointment".
Nigel Farage, who led Ukip's successful fight for Brexit, said he feared that "a betrayal may now be near at hand".
Unless overturned by the Supreme Court - or at a potential further appeal to the European Court of Justice in Luxembourg - the High Court ruling threatens to plunge the Government's plans for Brexit into disarray.
Brexit Secretary David Davis, who defended the Government's case in court, said ministers would be forced to produce a full Act of Parliament in order to trigger Article 50 unless the High Court ruling is overturned.
Mrs May's spokeswoman said it was still the Government's plan to invoke Article 50 by the end of March.
The Prime Minister will, at her request, discuss the Brexit process with European Commission president Jean-Claude Juncker on Friday, Mr Juncker's spokesman told reporters in Brussels.
The spokesman said all the other members of the EU would like to see a "swift" notification of Article 50 to begin the Brexit process.
Labour leader Jeremy Corbyn said the High Court ruling underlined the need for the Government to bring its negotiating terms for Brexit to Parliament "without delay".