While Keir Starmer’s authority as UK prime minister appears increasingly undermined—following calls from MPs and resignations by senior ministers—he remains at 10 Downing Street, for now, and still leads the Labour Party. So how—and when—could Starmer be removed as Labour leader? The Guardian’s Explainer outlines four plausible scenarios.
1. A Leadership Challenge Without Andy Burnham
Andy Burnham, mayor of Manchester and widely seen as the frontrunner among Labour MPs, is not currently a sitting MP. Any leadership challenge in the coming weeks would require an active MP to initiate it—either by securing support from at least 80 fellow MPs or by pressuring Starmer to set a timetable for his resignation.
Josh Simmonds, Labour MP for Makerfield, announced on Thursday, 14 May 2026, that he would step down from his seat to allow Burnham to stand in the resulting by-election. It remains unclear whether Downing Street will permit Burnham’s candidacy—and if so, whether he would win. If this path fails for any reason, a deadlock could ensue.
Wes Streeting, who resigned as Health Secretary on the same day, was reportedly prepared to launch a leadership challenge but failed to gather the necessary parliamentary backing. Other potential contenders—including Angela Rayner and Ed Miliband—do not appear to be mobilising fully at this stage.
That said, circumstances could shift rapidly—for instance, if newly released documents about Peter Mandelson’s proposed appointment as US ambassador reveal more damaging details. Notably, if a formal challenge is launched, Starmer would have the right to contest it—and could ultimately win the vote of Labour members.
2. A Leadership Challenge Following Burnham’s Return to Parliament
If Downing Street allows the Labour Party mechanism to back Burnham as the candidate in the Makerfield by-election, several weeks would pass before the vote takes place. A victory would return him to the House of Commons.
It is plausible that Starmer would permit Burnham to run—especially since Starmer previously blocked Burnham from standing in by-elections in Gordon and Denton. This time, however, mounting pressure could force a reversal.
Should a leadership contest follow, Starmer could choose to fight it—and might win. Labour uses the single transferable vote system, where members rank candidates by preference. It would not be unthinkable for Starmer to prevail in a three-way race, relying on second-choice votes from members reluctant to back either alternative.
3. A Slower, More Protracted Challenge with Burnham
This scenario envisions a longer timeline: Burnham first wins a seat via by-election, then builds momentum over months before formally challenging Starmer. Such a delay could allow Starmer time to regroup—or deepen internal divisions within the party, depending on how events unfold.