'We will meet the timetable I have set out' - Theresa May vows to trigger 'smooth and orderly' Brexit
Theresa May has vowed to trigger Brexit by the end of March 2017 even if the UK's highest court decides parliamentary approval is required.
The Prime Minister said the Government will "respect" the verdict of the independent judiciary, with the Supreme Court to announce its decision "as quickly as possible" in the new year.
Labour leader Jeremy Corbyn called on Mrs May to make sure her new year's resolution includes a "commitment to build better relations" with the UK's European partners to ensure she can secure the best deal possible.
The Supreme Court legal challenge from the Government emerged after a panel of three High Court judges decided in November that Mrs May lacked legal power to use the royal prerogative to trigger Article 50 of the Lisbon Treaty to start the two-year process of EU withdrawal.
Mrs May, updating MPs on last week's European Council meeting, said: "I'm clear the Government will respect the verdict of our independent judiciary.
"But I'm equally clear that whichever way the judgment goes we will meet the timetable I have set out.
"At the council I also reaffirmed my commitment to a smooth and orderly exit, and in this spirit I made it clear to the other EU leaders that it remains my objective to give reassurance early on in the negotiations to EU citizens living in the UK and UK citizens living in EU countries that their right to stay where they have made their homes will be protected by our withdrawal."
Mr Corbyn said Mrs May and the UK are becoming "increasingly isolated" on the international stage.
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He said: "As we move swiftly towards the triggering of Article 50, I want to appeal to the Prime Minister to not only work hard to heal those divisions in Britain but also to make sure her new year's resolution includes a commitment to build better relations with our European partners, so we get the best deal for the people of this country - not just a Brexit which benefits business and bankers.
"At the moment it's clear on the international stage the Prime Minister and Britain are becoming increasingly isolated."
The Opposition leader said his talks with European leaders have shown they are becoming "increasingly frustrated" by Mrs May's "shambolic Government and the contradictory approach" to Brexit negotiations.
He told the PM: "The mixed messages from your frontbench only add to the confusion. This Government fails to speak for the whole country.
"Instead we hear a babble of voices speaking for themselves and their vested interests."
Mr Corbyn raised contradictory statements from officials and ministers linked to the length of time needed to secure a Brexit deal and whether there will be transitional arrangements.
He added: "The people of Britain deserve better than this confusion at the heart of Government."
Mr Corbyn also claimed "confidence is being lost" as he pointed to Office for Budget Responsibility forecasts for 2017, noting growth, wages and business investment have been revised down.