Theresa May is ready to walk away from Downing Street in the summer if her Brexit deal gets passed, it was claimed today.
Allies of the PM believe she is preparing to trigger a leadership contest once the UK formally leaves the bloc - and prevent Boris Johnson taking over.
There has been mounting speculation that Mrs May will not carry on in No10 for long after March 29.
The premier was forced to concede that she will not fight the next general election in order to avoid a catastrophic Commons defeat at the hands of Brexiteers last month.
According to Cabinet ministers the Prime Minister has hinted to them she will trigger a Tory leadership race to end at the party's annual conference in October.
But she will announce it after Brexit, to give her time to pick and prep a replacement.
A source close to Liam Fox, May's good friend, told The Sun the current International Trade Secretary believes she will go after the deadline on March 29.
A senior Tory source said: 'Liam is convinced she'll go this summer. He says everything the PM has told him suggests that.
'She's determined to ensure the right person follows her, and she'll have no say at all if it gets to the stage of forcing her out.'
Mrs May has only dropped hints, however, and has not revealed to anyone what she will do.
A senior No10 source said it is only ever her husband who knows what she is planning.
They said to the same paper: 'The only person who will know Theresa's real thinking on when she'll step down is her husband Philip.
'She won't share it with anyone else, not us or any Cabinet minister.'
According to some in the Tory party Mrs May wants to leave when she has regained strength after the exit date.
However, she will take a keen interest in the person replacing her.
It is believed she will attempt to keep out those who have harmed her premiership, such as Boris Johnson.
Business Secretary Greg Clark has apparently also indicated to friends she will go this year.
However, this week BoJo softened on his stance which has been critical of the cabinet and their leader.
Former foreign secretary Johnson has insisted the so called backstop agreement with the European Union having a time limit on it would see him back May's deal.
However, his demand remains that the agreement would need to expire before the next general election in 2022.
Mr Johnson indicated he would be willing to accept a time limit on the backstop as his price for backing Theresa May's EU Withdrawal Agreement.
'The argument is now about how to get out of the backstop. And how to make sure that the UK isn't locked in that prison of the customs union,' he said.
'I think that you would need to have a time limit.'
But asked if changes to the backstop proposals could come in a separate codicil to the Withdrawal Agreement, Mr Johnson said: 'I don't think that would be good enough.'
The intervention early this week came as the PM moved to quell Tory fears that she is about to cave into Jeremy Corbyn's demand for a permanent Customs Union with the EU.
EU negotiator Michel Barnier today doubled down on demands Mrs May reach a deal with Mr Corbyn, insisting 'something has to give on the British side' and 'time is short' to conclude the deal.
Mrs May then caused panic in Tory ranks by appearing to open the door to a grand bargain.
But Downing Street insisted the PM was 'absolutely clear' that she will not support the call from Labour.
Mrs May sparked furore by penning a letter to Mr Corbyn saying his call for the UK to stay in a customs union would hamper free trade deals – but stopped short of ruling it out.
Mrs May also said the Tories were 'prepared to commit' to new laws to protect workers' rights after Brexit – a key demand of Labour and the unions.
But the hints at a cross-party pact, which could frustrate opposition from hardline Tory Eurosceptics, risked causing a Cabinet meltdown - with several senior figures including Liz Truss and Liam Fox thought to be ready to quit.
Brussels has so far flatly dismissed pleas from Mrs May to reopen the divorce package that they painstakingly thrashed out over two years, despite it being humiliatingly rejected by MPs last month.
Mrs May is now due to make a statement updating MPs on her progress renegotiating tomorrow, before the latest round of crunch votes are held on Thursday.
Treasury Chief Secretary Liz Truss yesterday refused three times to say whether she would remain in the Cabinet if a customs union became official policy.
Asked whether she would resign, she told Sky News: 'I absolutely do not think that should be our policy.'
Fellow Cabinet ministers Liam Fox, Andrea Leadsom and Penny Mordaunt are also said to be implacably opposed to any shift towards a customs union.
Dr Fox warned today that Labour proposals for a customs union with the EU are 'not workable'.
Brexiteer Andrea Leadsom dismissed the prospect of Mrs May adopting Jeremy Corbyn's 'world view', and insisted: 'I'm staying in Cabinet to help the Prime Minister deliver Brexit.'
Asked in an interview with the Press Association if she would resign if the PM adopted Labour's proposals for a customs union with the EU after Brexit, the Commons Leader said: 'I've read the Prime Minister's letter and I don't think she's softening her stance at all.
'I think she's making quite clear that what Corbyn is demanding is actually not as good as what the Prime Minister's deal is offering.
'So he wants a customs union and he is unclear as to whether that means he also wants an independent trade policy. He's unclear as to whether he also wants to stop free movement, and of course the EU's view would be well if you're in the customs union then you have free movement and you abide by the common external tariff.
'I think there's no doubt that what the Prime Minister is offering is better than what Corbyn is demanding, which simply begs the question, if they like it, why don't they vote for it?'
Pressed again on the issue, Mrs Leadsom said there was 'no chance' that Mrs May would adopt Mr Corbyn's 'view of the world'.
'The Prime Minister has been absolutely clear we're leaving the EU, we're leaving the customs union, we're leaving the single market.
'We're taking back control, we won't be paying money over, free movement will end, and we will have our own independent free trade policy so I definitely don't see the Prime Minister agreeing to Corbyn's world view.'
The frontbencher refused to say what the cut-off date would be for the necessary legislation to get through the Commons to allow the UK to leave the EU as planned on March 29.
This article has been adapted from its original source.
© Associated Newspapers Ltd.