Sir Keir Starmer has insisted that he isn’t going anywhere and will fight any attempts by his own party to oust him from No 10 after dozens of Labour MPs called for him to stand down.
But history is littered with prime ministers who have not been able to choose the time of their departure, from Margaret Thatcher to, more recently, Liz Truss.
Here we look at how the Labour leader could be forced out of Downing Street, ensuring the UK’s seventh prime minister in a decade.
Senior ministers start to resign
A number of ministers, including the high-profile Jess Phillips, have already resigned - and more are expected to go. But what the PM will really struggle to stand firm against ia a challenge from one of the “big beasts” tipped to replace him.
That could include health secretary Wes Streeting, who has so far has been reluctant to make the first move, aware that he would have to resign from the cabinet to do so.
That was what Rishi Sunak did, in a move that hastened the end of Boris Johnson’s premiership. But allies of Mr Johnson never forgave Mr Sunak for that and he faced accusations from Tory voters on the doorstep that he was a traitor.
The home secretary Shabana Mahmood is understood to have told the PM he needs to consider announcing a timetable for his departure, as has energy secretary Ed Miliband, although neither has resigned from cabinet to force the issue.
Other senior politicians not in the cabinet who could declare they want to stand in a leadership contest include Angela Rayner, although she is thought to still need more time to sort out her tax affairs. Andy Burnham cannot throw his hat in the ring yet because he is not in Parliament, which is why his supporters want a gradual timetable for Sir Keir’s departure.
Challenger gets the numbers to force a contest
The bar to trigger a leadership contest within the Labour Party is actually quite low. Although, of course, the stakes are high.
All that is needed is for an MP to secure the support of 20 per cent of the Parliamentary party – 81 MPs. More than that number have already gone public with their call for Sir Keir to go.
The prime minister automatically gets the right to fight the contest – and his allies have made it clear that he will.
Will there be a general election?
In a word, no.
The party of government gets to decide who their leader is, and they become the next prime minister.
There is no requirement to have a general election just because there is a new leader.
The demand for Sir Keir to stand down comes after disastrous local election results across England, Scotland and Wales last week, which saw both Reform and the Greens take millions of votes from Labour.
The party is in no mood to go to the polls again anytime soon.
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