What next for Starmer? Five scenarios in Labour leadership crisis

15 May 2026, 13:43

PA Media

Resignations and a revolt by some MPs this week have challenged Prime Minister Sir Keir Starmer's grip on power but there is still no clear resolution to the leadership crisis affecting Labour.

Andy Burnham is seeking to stand in a by-election triggered by the resignation of a Labour MP who wants the Greater Manchester mayor to replace Sir Keir.

Wes Streeting has also resigned as health secretary, saying he wanted a "broad" debate about the party's next leader.

Meanwhile former deputy prime minister Angela Rayner has not ruled out running in any race after saying that an investigation into her tax affairs had been resolved.

And yet there is no leadership contest.

It's a messy picture, so what are the possible scenarios in the coming weeks?

Starmer decides to stands down

Given the relentless pressure he's faced this week to stand down, the prime minister may decide he's simply had enough.

It seems unlikely at this point, though.

Many Labour MPs want him to set out a timetable for his departure, an option that could offer a more dignified and orderly exit at a time of Sir Keir's choosing.

But he has repeatedly said in recent speeches and to his cabinet that he would not "walk away" from the top job, suggesting he would fight any challenge.

There is a leadership contest without Burnham

In theory, an immediate leadership contest could be triggered by a Labour MP with enough support to challenge the prime minister.

They would need the backing of 20% of the parliamentary party - 81 Labour MPs - to start the process.

It was thought that Streeting could be the one to do this, until he declared - in his resignation letter this week - that he wanted a "debate about what comes next".

His allies said he did have the numbers necessary but decided to put pressure on the prime minister to quit on his own terms rather than hurtle into a contest right now.

But the prime minister's supporters have suggested Streeting was nowhere near the number of MPs he needed, with one estimating that he only had 44 committed backers.

Either way, it looks like Streeting is biding his time, meaning a drawn-out battle.

In a post on social media, he appeared to support allowing Burnham to stand as the party's candidate in the Makerfield by-election, saying he had "the best chance of winning".

Burnham wins the by-election and Starmer fights him for the leadership

This scenario involves a leap of imagination.

There is no guarantee that Burnham will win the Makerfield by-election, which will be hotly contested by Reform UK. It's a big gamble for Burnham as he can only mount a challenge for the Labour leadership if he's an MP.

But if he manages to pull that off, he would be able to argue he has proof that he could revive Labour's deflated standing in the opinion polls and beat Reform UK in a general election.

In contrast, Sir Keir has a pretty poor record against Reform UK, which pummelled Labour in some of its historical strongholds in last week's elections in England, Scotland and Wales.

Back in Parliament, Burnham could mobilise the necessary support to trigger a leadership contest and take that electoral evidence into the campaign.

In a head-to-head with Sir Keir, who has just lost hundreds of council seats and February's Gorton and Denton by-election to Reform UK, Burnham would have the wind in his sails.

If such circumstances come to pass, they could set Burnham on a course to No 10.

Burnham wins by-election and Starmer steps down

A Burnham victory in Makerfield would send a clear signal to Sir Keir, though.

The prime minister would probably be aware that polling of Labour members suggests he would lose in a one-on-one leadership contest against Burnham.

Rather than put himself through the pain of a probable defeat, Sir Keir may leave office in the wake of Burnham winning the by-election.

That could either pave the way for his coronation as the new leader, or fire the starting gun on an election involving Streeting, Rayner and possibly other contenders.

Burnham loses by-election and all bets are off

There's every chance that Burnham could lose the Makerfield by-election.

Reform UK came a competitive second in the constituency in the 2024 general election, and last week won 24 seats on Wigan Council, including in two wards in Ashton-in-Makerfield.

Knowing this, Nigel Farage's party is feeling bullish about its by-election prospects.

If Burnham loses, all bets are off and the paralysis at the top of the Labour Party would enter a new and uncertain phase.

Sir Keir's time in Downing Street would almost certainly be extended in this scenario, putting the onus on a Labour MP or a cabinet minister, instead of Burnham, to mount a leadership challenge.