British Prime Minister Keir Starmer was considering his ​political future on Sunday, after rival Andy Burnham‘s decisive election victory to parliament prompted more ministers in the governing Labour ‌Party to call for him to go.

Struggling with some of the lowest popularity ratings for any British leader, Starmer could decide as soon as Monday whether to step aside or fight a leadership contest against Burnham, one source said.

The scale of victory Burnham won for a parliamentary seat in northwestern England on Friday has piled ​pressure on Starmer, with dozens of lawmakers and some ministers privately calling for him to set out a timetable for his ​departure to clear the way for the former mayor.

A source with knowledge of the matter said Starmer was ⁠spending the weekend thinking about and discussing his position with his family but that an expected conversation with Burnham would clarify matters.

“Keir likes ​to think about things,” the source said.

Starmer’s unpopularity was laid bare by Labour’s heavy losses in local elections in May, and polls of party members ​indicate Burnham would win a formal leadership contest.

Should Burnham take the helm, he would become Britain’s seventh prime minister in the past 10 years.

Starmer’s position under threat

Sky News reported that it understood foreign minister Yvette Cooper had called on Starmer to stand down in a private conversation over the weekend. Her spokesperson did not ​immediately respond to a request for comment.

Her apparent appeal, alongside other ministers and dozens of lawmakers, increased the sense that it was now ​a case of when, rather than if, Starmer would step aside.

Starmer said only a few days ago that he would stand in any formal Labour leadership contest ‌that sought ⁠to replace him.

While Starmer’s team believes his landslide national election win in 2024 gives him the mandate to stay in post until 2029, business minister Peter Kyle said the prime minister was reflecting on “the political challenges that he faces in this moment”.

Kyle said he had spoken to Starmer on Friday and had found a man who was questioning what “the country expected of him”. The conversation showed Starmer was in “very difficult ​circumstances”, the business minister said.

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“So I’m ​not going to deny the ⁠political challenges that he faces in this moment, but what I’m also not going to do is say there is ever anything inevitable about the days ahead,” Kyle told LBC radio.

Starmer’s position is precarious.

Burnham’s thumping ​win over the populist Reform UK party to take a parliamentary seat in Makerfield prompted more lawmakers ​and ministers to ⁠press the prime minister to set a timetable for his departure to avoid what could be a divisive leadership race.

The team supporting Burnham, a 56-year-old career politician and former Greater Manchester mayor, had said they were giving Starmer the weekend to consider his position in the hope that he would ⁠set out ​an orderly transfer of power.

As yet, there was no indication that the two had spoken.

Former ​minister Jess Phillips, who is a supporter of health secretary Wes Streeting, another potential challenger to Starmer, told the BBC that “it feels like we’ve come to the end of the ​road” and that it would be best for Starmer’s departure to be “as dignified as possible”.