Chairman of the 1922 Committee Sir Graham Brady announced the results in the Houses of Parliament this evening.
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James Cleverly MP for Braintree and deputy chairman of the Conservative Party said:"Clearly I'm disappointed that some in my party have triggered a vote of no confidence just as the PM is having a series of worldwide meetings to deliver Brexit".
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Labour did not table a motion of no confidence after Mrs May pulled the Commons vote on her Brexit deal, preferring to wait on the sidelines while Tory MPs fought among themselves.
And there were gasps of shock from the supporters of Mrs May.
The Prime Minister was all smiles when she arrived back at 10 Downing Street after the ballot closed, though.
She has suggested the Government is looking at how to give "democratic legitimacy" to the backstop through giving MPs a vote on it and enabling the Commons to force the Government to ensure it can not be in place "indefinitely".
"This has been a long and challenging day", she said.
West Suffolk MP and Secretary of State for Health and Social Care Matt Hancock said: "I'm voting for the Prime Minister tonight and urge all colleagues to do the same". "Some of the suggestions she made sense, others I thought were hard", he said.
He added: 'Now we must get on with the job of delivering a successful Brexit and our domestic priorities including a strong economy.
Speaking immediately after the result of the vote was declared, the Tory Brexiteer said: "The Prime Minister must realise that under all constitutional norms she ought to go and see The Queen urgently and resign". German chancellor Angela Merkel will step down shortly, French president Emmanuel Macron and Polish prime minister Mateusz Morawiecki are facing no confidence votes and the Belgian prime minister is now leading a minority government. "She should make way for someone who does".
May, who made a last-minute promise not to take part in 2022 electoral campaign, "obviously helped her cause by promising her party that she won't lead them into the next election", Szamuely believes.
She said: "A change of leadership in the Conservative party now would put our country's future at risk and create uncertainty when we can least afford it".
"She must now bring her botched deal back to Parliament next week".
Mrs May had meetings with European leaders on Tuesday, seeking support for changes to her Brexit deal in a last-ditch bid to save it.
Mrs May appeared rustled when she was asked by the media if she had been made aware of a vote of no confidence after meeting European Union president Donald Tusk in Brussels last night.