LONDON — A would-be stalking horse candidate to replace British Prime Minister Keir Starmer backed away from the nuclear option of launching a leadership bid Monday.

In an interview with POLITICO, Catherine West said she is now seeking support from MPs to force the British prime minister to hold a leadership election by September — a move she described as a “less threatening” way to build support for Starmer’s departure.

West’s decision means the immediate threat to Starmer has receded — but his position in No. 10 Downing Street remains in peril.

West on Saturday stunned Westminster by saying she would trigger a Labour leadership contest unless Starmer’s Cabinet moved against him by Monday. But she backed away from that threat in a letter sent to Labour MPs shortly after Starmer said he has no plans to resign during a speech in London.

“It gives me a little bit of a breather, take stock and this way you’re formally asking somebody that they think there should be a change, so it’s a step before that. For new MPs, for example, it’s far less threatening to say you want that,” West said. 

Her U-turn gives potential leadership challenger Andy Burnham, who does not currently have a seat in Westminster and is the mayor of Greater Manchester, time to return to parliament as an MP.

Angela Rayner, another potential contender, also still has to resolve the tax issue that forced her resignation as deputy prime minister.

In another boost to Burnham, Rayner told an audience of union reps Monday that the Greater Manchester mayor should not have been blocked from returning as an MP earlier this year. Only Wes Streeting appears close to being ready to run a leadership contest — but MPs on the left of the party would likely challenge any move from the health secretary.

West said “proxies” for each of the three leadership camps had contacted her since she threatened a putsch.

She admitted she had given little thought to running for prime minister herself before delivering her ultimatum to Starmer on Saturday.

“The benefit of doing it this way is, the whole way I’ve maintained I’m not supporting a particular camp. But if I was going to do it, it would be my camp wouldn’t it? And I have had somebody say I’ll be your chief of staff, you’ve got to run for PM. But that would require a lot more thought on my part,” she said.

West clarified she wants a contest to “begin soon, but finish by September” — contrary to what she said in her letter to MPs.

“I shouldn’t have written ‘in’ [September], I should have written ‘by’,” she said of her letter to MPs. 

West said she would not make the names of those calling for the leadership contest public “for now,” giving MPs more cover to challenge the PM without going for a more high-stakes and public option.

She would update Labour Party Chair Anna Turley before asking if she could make MPs’ names public, she said.

“The threshold for my candidacy would’ve been 82, so that might be a good guide,” she said to POLITICO of the timing of when she would seek to make public the scale of support for a leadership contest. 

“There will be people that get very upset but I think the emotional cost for us now is worth the X in our box on polling day in 2.5 years because we have to beat [Nigel] Farage,” she said.

POLITICO’s tally of MPs publicly calling for Starmer to go reached 46 on Monday afternoon.