British Prime Minister Keir Starmer is understood to be preparing to resign, paving the way for Andy Burnham to replace him.His departure would mean the arrival in Downing Street of the UK's seventh Prime Minister since the country voted to leave the EU 10 years ago this week. That level of turnover - the highest in Britain ​for nearly two centuries - underlines the struggle of maintaining the support of voters angry at successive failures to improve living standards, public services and tackle illegal immigrationA statement from the prime minister setting out a timetable for his departure could come as early as Monday, although nothing has been confirmed. Brexit chaosIt would mark a remarkable turnabout for Mr Starmer who less than ​two years ago won a landslide election victory that promised to end Britain's chaotic politics and returned Labour to power after 14 years out of office. After the chaos of the post-Brexit years — when the Conservative Party cycled through David Cameron, Theresa May, Boris Johnson, Liz Truss and Rishi Sunak as their leader — Mr Starmer had come to power promising a new era of stability.Media gather outside 10 Downing Street in anticipation of a statement from British Prime Minister Keir Starmer. ReutersInfoHowever, he spent the weekend considering his position and whether he should continue to fight attempts by Mr Burnham, who was elected to Parliament last week, to depose him.The threat to Mr Starmer, which has been building for months, increased sharply on Friday when Mr Burnham, the Greater Manchester mayor, decisively won a parliamentary election ⁠to return to Westminster, beating a candidate from Nigel Farage's Reform UK party which has led national opinion polls for more than ​a year.That victory ⁠gave hope to Labour MPs that Mr Burnham, who held posts in the Blair and Brown governments and portrays himself as a 'man of the people', could transform the fortunes of a party that has lost support under Mr Starmer, whose popularity ratings have ​sunk to the lowest for any British leader.Mr Burnham is due to make his return to Westminster on Monday to be sworn in as the Makerfield MP and is expected to press Mr Starmer to set out plans to stand down.Cabinet warningsMr Starmer is reported to have been told by members of his Cabinet, including Foreign Secretary Yvette Cooper, that he should set out a timetable for ceding power.No 10 said Mr Starmer’s position remained unchanged from Friday, when he said he would not “walk away” from Downing Street and will stand in any potential contest.The Prime Minister will “make his own decisions” about whether to resign, a minister said on Monday.Education minister Baroness Jacqui Smith said her understanding was that Mr Starmer had spent the weekend “thinking really carefully about the future of the country, about what’s the best thing to do for the British people”. She said he puts that “ahead of the interests” of the Labour party.Cabinet minister Peter Kyle did not shut down questions of Mr Starmer considering quitting as he spoke to broadcasters on Sunday.The Business Secretary said the Prime Minister was taking time to “think through what the political realities are today compared to last week, the week before”.US President Donald Trump said in a post on Truth Social on Sunday that Mr Starmer “will resign” as prime minister. A UK official said that nothing had been communicated to Trump from the government and he had not spoken to Starmer. Andy Burnham celebrates his victory in Friday's Makerfield by-election. Getty ImagesInfoRoute to powerIt is understood that Mr Burnham is looking for a transition of about a month, which would give Mr Starmer time to get his Defence Investment Plan over the line in time for the upcoming Nato summit and sign his planned EU co-operation deal at the second annual reset summit with the bloc in July.It is thought Mr Burnham’s camp would however accept a timetable that sees Mr Starmer in No 10 until September.Questions are being raised within Labour about how a change of leader would come about – with some backing a leadership contest and others a swift transfer of power to Mr Burnham.York Central MP Rachael Maskell said she thought “a smooth transition and handover” over the next month would be best.“I think it’s widely believed that even if there was a contest, that Andy Burnham would win that with a considerable majority, and therefore I do question why we need to go through that process,” she said.Labour peer Baroness Harriet Harman suggested the Parliamentary Labour Party could endorse Mr Burnham to give him some “legitimacy” if there are no other candidates.Former health secretary Wes Streeting suggested last week he was willing to trigger a contest and had the backing to do so, but there has since been speculation he could instead make a deal for a role in Mr Burnham’s Cabinet.Play01:25Burnham win rattles Labour leadershipResignation callsThe number of Labour MPs calling for Mr Starmer to go has topped 100 – just under a quarter of the party’s cohort in the Commons – and includes some who signed a letter warning against a leadership contest just last month.But the widely expected change of leader is not without risk. Beyond saying that the country needs fundamental change and to bring down the cost of living, Mr Burnham has yet to make clear his approach to foreign affairs, the economy and defence. Like Mr Starmer he could find he has little room to manoeuvre, hemmed in by bond market investors opposed to any additional borrowing, and confronted by an angry electorate who believe the country is not working properly. Britain already has the highest borrowing costs in the Group of Seven wealthy nations due to its high debt and interest payments, years of anaemic economic growth, its struggles to cut spending and the need to invest in areas like defence.Last September Mr Burnham said that Britain had to get "beyond this thing of being in hock to the bond markets" would respect the need to reassure markets.He has since said he was misrepresented."In our view, a Burnham premiership would inherit a precarious fiscal situation with few tools to deliver meaningful change," economists at Citibank said on Friday.A senior Conservative said there would not need to be a general election if Mr Starmer resigns, but added replacing the Prime Minister would not solve Britain’s problems.Alex Burghart, the shadow Cabinet Office minister, told BBC Radio 4’s Today programme on Monday: “Constitutionally there doesn’t have to be a general election, you can change prime ministers.“What matters is whether the prime minister has the support of MPs in Parliament.“But I have to say that there, it’s not just Keir Starmer’s legitimacy that is being called into question, it’s Labour’s.“You can change the person at the top, but if the MPs underneath still think and vote the same way, then nothing will change.”