Theresa May is expected to fire the starting gun on a Tory leadership race imminently by confirming her plans to stand down as prime minister.
Sky News understands she will finally bend to the pressure of backbenchers and ministers and name the date of her departure from Number 10 later today.
Downing Street has not confirmed the move.
Mrs May is braced for a showdown this morning with Sir Graham Brady, chair of the 1922 committee of all Tory MPs.
She will be asked to confirm when she plans to resign, regardless of whether her flagship Brexit legislation to transform her deal into law passes in parliament.
If the prime minister refuses, Sir Graham will open a sealed letter containing the results of a ballot from the 1922’s executive committee about whether to change party rules to force her out.
The immunity she has from a Tory rebellion until December could crumble if a majority agree to allow another no-confidence vote.
The current plan, Sky News’ political editor Beth Rigby said, is for the prime minister to make an announcement after the meeting.
Mrs May is likely to want to remain in power until US President Donald makes his state visit to London, which runs from 3-5 June.
A senior source told Sky News that the prime minister wanted to get though the visit before starting the leadership race, with the insider saying that June 10 is the most likely exit date.
“I want to give her a graceful exit to pay tribute to what she’s done for the party, and that would be much tidier,” Sir Geoffrey Clifton-Brown, treasurer of the 1922 committee, told Sky News.
“But if she’s stubbornly going to stick in there, then it may be necessary for the 1922 to give the party a vote on this matter.”
Immediately after Mr Trump’s visit will be the Peterborough by-election, and the potential vote on her Withdrawal Agreement Bill (WAB), which she says is MPs’ “last chance” to deliver Brexit.
Today marks the end of a frenzied week for Mrs May, after more MPs came out to demand her immediate resignation and a senior cabinet minister quit, sending shockwaves through the government.
Brexiteer Andrea Leadsom said she could not support the revamped WAB because it did not respect the referendum result.
The prime minister’s compromise bid, which includes votes on a type of customs union and another EU referendum, enraged many in her party.
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