Reform UK leader Nigel Farage has demanded a snap general election if Sir Keir Starmer is toppled as Prime Minister.
Sir Keir, who is expected to face a leadership challenge from ex-Health Secretary Wes Streeting, could soon come up against Andy Burnham as the Greater Manchester Mayor plots his return to Westminster on the campaign trail in Makerfield.
However, Mr Farage warned the public is growing tired of governing parties changing their leaders without a vote.
Asked whether a snap election should be held if Labour changed leader, the Clacton MP told The Telegraph: "Yes. The public have had enough of Prime Ministers constantly changing.”
Almost 100 Labour MPs have called on Sir Keir to set out his timetable to leave Downing Street.
However, the possibility of Sir Keir's departure makes it increasingly likely the UK will have its seventh Prime Minister in little over a decade.
David Cameron's six years in power between 2010 and 2016 have been followed by stints of just over three years for both Theresa May and Boris Johnson, 49 days for Liz Truss and 20 months for Rishi Sunak.
A departure anytime soon would also make Sir Keir the shortest-serving Labour Prime Minister.
Reform UK leader Nigel Farage wants a snap general election
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The ex-lawyer, who only entered the House of Commons in 2015, has spent just 690 days in Downing Street since the 2024 General Election.
Meanwhile, Gordon Brown served as Prime Minister for 1,048 days, with James Callaghan's no-confidence defeat ensuring his tenure lasted 1,129 days.
However, there is no obligation to hold a general election if there is a change of Prime Minister.
Mr Brown refused to call a snap poll after succeeding Sir Tony Blair in 2007, prompting cries that the former Chancellor had "bottled it".
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Sir Keir Starmer is facing a potential challenge to his leadership
| GETTYMr Farage's call for a snap general election came shortly after a Labour veteran issued a similar warning to Sir Keir's potential leadership rivals.
Baroness Harman, who is Sir Keir's new adviser on women and girls, said: “There is a scenario in which the new leader – call him Andy Burnham, for example – actually thinks ‘I need a new mandate’.
“And Farage will be saying: ‘Well, yes, the country does want a new prime minister but they want me – nobody’s voted for him, he’s a usurper.’
"And it might be that he [Burnham] thinks he’s got to get his own mandate rather than just manage the implementation of Keir Starmer’s mandate.
Andy Burnham is hoping to become the next Prime Minister
| GETTY“And, if he had a big surge in the polls, he might think he should go for a general election and not do what Gordon Brown did… So we might find ourselves not only with a new Prime Minister, but somehow tipped into a new general election.”
Conservative insiders have also started preparing for an early general election.
"The fear is that it will catch us completely off guard," a Tory source told The Daily Mail. "We are not ready."
An opinion poll conducted by More in Common found support for Reform UK stands at 30 per cent, with Labour languishing behind in a distant second on just 20 per cent.
Reform UK leader Nigel Farage could win the most seats, according to new polling
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Kemi Badenoch's Tories secured just 19 per cent of the vote in More in Common's poll, with the Green Party's support standing at 13 per cent and the Liberal Democrats flatlining on 12 per cent.
However, the same pollster recently released research which suggested Mr Burnham could turn around Labour's electoral fortunes.
Labour would receive an eight-point boost with Mr Burnham as leader, leading to a two-point drop in Reform UK's support.
Such a scenario could result in a hung parliament, raising the possibility of a progressive coalition to keep Reform UK out of power.