Parliament's vote on British Prime Minister Theresa May's Brexit deal will go ahead on December 11, her office said on Thursday, despite a newspaper report ministers had sought a delay to prevent a defeat so big that it might bring down the government.
She suggested MPs could be "given a role" in deciding whether to activate the backstop, which is created to stop the return of a physical border.
Mrs May told them: "I promise you today this is the very best deal for the British people, I ask you to back it in the best interests of our constituents and our country".
He said he had already been given authority by his local party's executive to submit a letter to Sir Graham Brady, the chairman of the party's backbench 1922 Committee, seeking a vote of no confidence in Mrs May.
Surviving Brexit in a town that voted to leave.
May also took aim at those in Parliament that she said were trying to "frustrate Brexit".
The backstop, meant to prevent the return of a hard border in Northern Ireland, is highly controversial as Brexiteer MPs claim it traps the United Kingdom into obeying rules set by Brussels without a say over them.
Shadow home secretary Diane Abbot said: "On the question of security, assertions, aspirations, a wish list is not enough, we need a treaty".
Fylde's Conservative MP Mark Menzies has called for calm in the Brexit debate - saying he supports the Prime Minister, but is not convinced by the deal on the table at present.
Marcos ROJO plays in first Manchester United match against Arsenal since May
There is, however, a first league start for Diogo Dalot and returns in defence for Chris Smalling and Eric Bailly. Meanwhile the Spaniard warned that the diagnosis for Rob Holding's knee injury "is not good".
We have delivered a deal that honours the vote of the British people.
European Union negotiator Michel Barnier said on Thursday the deal was the best Britain will get, while British finance minister Philip Hammond said it was "simply a delusion" to think the agreement could be renegotiated if parliament rejects it.
"The idea of renegotiating at the 11th hour is simply a delusion", Hammond told Parliament.
It would add provisions for the Commons to "approve the Government's proposed approach, including whether or not an extension to the implementation period should be pursued; and parliamentary approval of the commencement of the powers implementing the Northern Ireland backstop".
"The alternative is uncertainty and risk - the risk Brexit could be stopped, the risk we could crash out with no deal".
The document was described as "devastating" by the Democratic Unionist Party, the small Northern Ireland party that has been propping up the UK Prime Minister in parliament.
Mr Javid continued: "They would have fewer options for pursuing criminals across borders, as we would lose our efforts through Europol and Eurojust, and it would take longer to track, arrest and bring to justice those who commit crimes internationally".
Chief whip Julian Smith acknowledged he faces an "uphill challenge" to persuade MPs to back Mrs May's deal, but insisted "it's all to play for".
Labour leader Jeremy Corbyn said Mrs May's deal would "make this country worse off".
"I believe we are still looking at an outcome that is, as yet, to be determined; there is a deal on the table which I do not think in its current form will make it through Parliament".