Cabinet meetings have been called for Monday morning, with reports the Prime Minister could be forced to resign within days amid a furious backlash over her handling of Brexit.
Backbench Tory Brexiteers including Boris Johnson, Dominic Raab, Jacob Rees-Mogg, David Davis and Iain Duncan Smith will meet Mrs May at Chequers on Sunday afternoon, with calls mounting for her to quit.
Cabinet Office minister David Lidington, who has been tipped to head a possible caretaker administration to get a Brexit deal through parliament, told reporters in his Aylesbury constituency: "I don't think that I've any wish to take over from the PM, who I think is doing a fantastic job.
"I have absolute admiration for the way she is going about it."
The Sunday Times reported 11 Cabinet ministers had told the paper they wanted Mrs May to make way for someone else and that the PM's de facto deputy David Lidington was in line to take over the helm.
But the Mail on Sunday reported ministers were plotting to install Environment Secretary Michael Gove as a caretaker leader.
Mrs May's former policy adviser MP George Freeman said it was "all over for the PM", tweeting: "She's done her best. But across the country you can see the anger.
"Everyone feels betrayed. Government's gridlocked. Trust in democracy collapsing. This can't go on. We need a new PM who can reach out [and] build some sort of coalition for a PlanB."
Pro-EU former education secretary Nicky Morgan told the Sunday Telegraph that Cabinet ministers should tell Mrs May "it's time to go" while Brexiteer Steve Baker said potential leadership contenders in the Government should "act now".
Tory backbencher Anne-Marie Trevelyan wrote in the same paper: "We now need a leader who believes in our country and wants to take her on the next stage of her journey."
The Chancellor told Sky’s Ridge on Sunday programme that replacing Theresa May would not "solve the problem".
After another turbulent week for the Prime Minister which saw her come under fire for delaying Brexit and seeking to blame MPs for the impasse, the Commons was expected to be given the third chance to vote on her Withdrawal Agreement this week.
But on Friday night Mrs May wrote to parliamentarians warning if there is insufficient support for her Withdrawal Agreement in the coming days that she could seek an extension to Britain's EU membership beyond the European Parliament elections.