THERESA May has seen off a coup attempt by Brexiteer Tories but her authority suffered a serious blow after more than a third of Conservative MPs said they did not have confidence in her.

The scale of the parliamentary task the Prime Minister faces to get her Brexit deal through the Commons is stark as adding the 117 Tory rebels to the number of opposition MPs who could vote against her plan produces a Commons total of 439 compared to just 200 Tories who support her.

Nicola Sturgeon said the result showed Britain now had a “lame duck Prime Minister saddled with a lame duck Brexit deal”.

Damian Green, the PM’s former de facto deputy, said his leader had achieved “a very good result," stressing: "Two hundred is above anyone’s expectation. It’s absolutely decisive.”

But arch Brexiteer Jacob Rees-Mogg, Chairman of the anti-EU European Research Group, said the result was "terrible" for Mrs May.

Noting how more than half the Tory backbenchers beyond the Government payroll had voted against her, the Somerset MP said: “Of course I accept this result but the Prime Minister must realise that under all constitutional norms, she ought to go to see the Queen urgently and resign.”

Nigel Dodds for the Democratic Unionist Party, tweeted: "The message from tonight is very clear. The backstop must go."

After the result was announced, Mrs May acknowledged that a "significant" number of Tory MPs had voted against her but she insisted: “Following this ballot we need to get on with the job of delivering Brexit for the British people and building a better future for this country."

She urged politicians on all sides to come together and act “in the national interest" and said when she goes to the European Council today she will be “seeking legal and political assurances that will assuage the concerns” MPs have on the backstop.

The result of the confidence vote was 200 for the PM and 117 against her; a majority of 83.

It came after she made clear to the Conservative Party that she will not lead it into the 2022 General Election. This throws up the prospect that Mrs May could leave office after Brexit Day in the spring.

Failure in the ballot would have triggered a damaging leadership contest in which the PM would not have been able to stand. Yet her victory means, another challenge can now not be mounted against her position as party leader for another year.

Speaking from Downing St after the result, Mrs May claimed she had a "renewed mission; delivering the Brexit people voted for, bringing the country back together and building a country that really works for everyone".

But the First Minister noted how almost 40 per cent of the PM’s parliamentary party had voted against her, which in any normal circumstance would make the Conservative leader’s position untenable.

“This result is barely even a pyrrhic victory for the Prime Minister, who has now admitted her time in office is limited,” declared Ms Sturgeon. “She may have clung on to the Conservative leadership but her remaining authority has been fatally undermined.”

The FM added: “The cost to Scotland of being under Westminster control and at the mercy of a Tory civil war has never been clearer.”

Jeremy Corbyn insisted the Tory confidence vote would make no difference to ordinary people’s lives. He called on Mrs May to “bring her dismal deal back to the House of Commons next week so Parliament can take back control”.

Pressure continues to mount on the Labour leader to call a confidence vote in the Conservative Government. His spokesman declined to say if this could happen on Thursday but stressed it was a matter of “not if but when”.

Despite the PM’s victory, the parliamentary impasse to her Brexit Plan remains.

Downing Street sources made clear that after her whistle-stop tour of European capitals this week, Mrs May still did not have the “further assurances” on the backstop she was seeking from the EU.

Today, the PM will travel to Brussels for a Brexit summit, having told colleagues at Westminster that she knows she has to return with something in the coming weeks that will satisfy the concerns of Northern Ireland’s Democratic Unionists to ensure the UK-EU deal gets through the Commons.

Another dramatic day at Westminster saw just 12 hours elapse from when Sir Graham Brady, Chairman of the Tories’ backbench 1922 Committee, announced the 48 letters calling for a confidence vote in Mrs May’s leadership had been received, to when he read out the result.

In a packed Commons Committee Room 14, the Cheshire MP waited dutifully for the clock to strike 9pm before he pulled an envelope from his jacket pocket. Surrounded by 1922 Committee colleagues, he first declared that the result showed the party continued to have confidence in Mrs May as their leader.

MPs stood, cheered and applauded.

Outside the committee room, Sir Alan Duncan, the Europe Minister, declared: “Job done. Move on.” Colin Clark, the MP for Gordon, described it as “a comfortable win and we should now deliver Brexit”.

Damian Hinds, the Education Secretary, said it was a “very clear result” and added that Mrs May was "batting for Britain and we need to be batting with her".

But Brexiteer Andrew Bridgen told The Herald: “It doesn’t make getting the deal through any easier. It doesn’t resolve any of the issues. The parliamentary party has merely kicked the can down the road and we’re running out of road.”

Fellow Leaver Mark Francois claimed the PM had suffered a “devastating result”. He explained: “She has lost support of well over a third of her party and well over half of the backbenches because the Government payroll vote is 140.”

Stressing he was not calling on his leader to resign, he added: “The PM will have to consider very carefully what she does now because to have well over 100 of your colleagues vote against you is not good news.”

Eurosceptic former Cabinet minister Owen Paterson tweeted: "V poor result for PM - setting aside the payroll, she has secured well under half of the backbench vote. She must now listen to those of us concerned that she is failing to deliver our clear manifesto pledges to leave single market, customs union and remit of ECJ."

A spokesman for the European Research Group of eurosceptic Tory MPs said: "The parliamentary arithmetic remains unchanged. We cannot and will not support the disastrous Withdrawal Agreement the Prime Minister has negotiated.”

But one Tory loyalist said he hoped the PM’s victory would “drive a stake through the heart of the ERG”.