Theresa May will still trigger Article 50 by end of March 2017 despite embarrassing Brexit High Court defeat, says No10

DOWNING Street claim their plans to trigger Article 50 by the end of March 2017 haven’t changed despite an embarrassing High Court defeat.

Theresa May will now have to go through Parliament before she can kick-start the process of leaving the EU, rather than push it through all by herself.

The bombshell ruling by the Lord Chief Justice this morning potentially threw her plans into disarray, but Number 10 were holding firm.

"Our plans remain to invoke Article 50 by the end of March," the PM's spokesperson told journalists.

"We believe the legal timetable should allow for that."

But the Government has declined to give a statement to the House of Commons, on the legal challenge, spearheaded by Gina Miller.

Instead the Prime Minister will update MPs next week on the judgement, which said her arguments had been contrary to “fundamental constitutional principles of the sovereignty of Parliament”.

The ruling said: “The court does not accept the argument put forward by the government. There is nothing in the text of the 1972 Act [to join the EU] to support it."

Mrs May is now appealing the decision to the Supreme Court, with a new hearing expected to be held in December.

Downing Street later said its expectation was that there would be no possibility of appealing to the European courts if it lost in the UK’s highest court, as the issue at stake was a question of British constitutional law and not a disputed point of EU law.

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.

He said all the other members of the EU would like to see a "swift" notification of Article 50 to begin the Brexit process.

But the timetable she laid out at Conservative Party conference last month seems unlikely to go ahead, with one QC warning Brexit could be pushed back until “after 2020”.

Leading lawyer Geoffrey Robertson said: “Today’s judgement emphasises that democracy means representative democracy and it is for MPs, voting according to their consciences and what they think is good for the country, to take us out of a constitutional arrangement that they took us into 40 years ago.

“I expect the Supreme Court will uphold today’s decision, which in my view is correct and obvious.

“If MPs have any guts and integrity, they will vote against Brexit until there has been a second referendum.

“I expect the House of Lords will certainly do this, so that Brexit, if it ever happens, will be delayed probably until after the 2020 election.”

The Brexit Secretary has also admitted there will need to be an new law enacted to trigger Article 50.

David Davis let slip he thought the Government would be forced into passing so-called 'Primary Legislation', meaning it has to be agreed by both Houses of Parliament, to kick-start the formal EU exit process.

The Cabinet minister said he was confident the Government's appeal would be successful, but said as of now triggering Article 50: "We’re presuming it requires an Act of Parliament."