Theresa May has promised Tory MPs she will stand down if they back her EU withdrawal deal.
She told backbench Tories: “I am prepared to leave this job earlier than I intended in order to do what is right for our country and our party.”
The PM said she knew that Tory MPs did not want her to lead the next phase of Brexit negotiations “and I won’t stand in the way of that”.
She did not name a departure date at a packed meeting of the 1922 committee.
It comes as MPs seize control of the Commons agenda to hold votes on alternatives to the deal.
Mrs May told the 300 or so Tory MPs at the meeting “we need to get the deal through and deliver Brexit”.
“I ask everyone in this room to back the deal so we can complete our historic duty – to deliver on the decision of the British people and leave the European Union with a smooth and orderly exit.”
Speaking after the 1922 committee meeting, Tory MP James Cartlidge said: “My recollection is that she said she would not remain in post for the next phase of the negotiations, the implication being that once the withdrawal agreement has passed, she would make way for someone else.”
Mrs May’s critics don’t want her to be still in charge for the next phase of Brexit talks, when the two sides hammer out what kind of trading relationship they will have – if her deal is passed by Parliament.
The PM has said she wants to bring the deal back to the Commons this week, after it was previously rejected twice, by large margins.
The BBC’s Iain Watson said Mrs May received a “muted” reception from Conservative MPs as she arrived at the meeting.
Speaker calls for changes
Commons Speaker John Bercow ruled last week that the government could not return for a third attempt, unless there had been “substantial” changes to the proposals.
And he warned ministers earlier that they should “not seek to circumvent my ruling” by introducing procedures that could reverse his judgement.
But a Downing Street spokesman said there had been a “significant development” at the summit in Brussels last week, after Mrs May agreed “extra reassurances” over the Irish backstop with the EU, and the date of exit had changed.
Many Tory Brexiteers are looking to the Democratic Unionist Party, who have led opposition to the PM’s deal, before deciding whether to get behind it.
Jacob Rees-Mogg, the chairman of the European Research Group of Tory Brexiteers, told the BBC: “I think that we have got to the point where legally leaving is better than not leaving at all.
“Half a loaf is better than no bread.”
He said his only condition for supporting the deal was that Mrs May wins round the DUP.
“I won’t abandon the DUP because I think they are the guardians of the union of the United Kingdom,” he said.
Brexit: Theresa May vows to stand down after deal is passed}