Streeting denies plotting against PM after leadership claims

"Someone has definitely been watching too much Celebrity Traitors. They should swap to Countryfile," he said.

Streeting was doing a round of media interviews on a morning, with headlines dominated by the briefings from the prime minister's allies.

The health secretary insisted he was "not challenging the prime minister" adding: "I'm not doing any of the things some silly briefer said overnight."

He said the culture in No 10 was "toxic" and that Lucy Powell, the party's new deputy leader, had been right to call for a change of culture in Downing Street.

"I'd like to commend the briefer on at least picking on one of the men in the cabinet instead of the women," he added.

Asked if he should sack those responsible, Streeting said: "Yes. But he's got to find them first and I wouldn't expect him to waste loads of time on this.

"There are people around the prime minister who do not follow his model and style of leadership."

Other names being discussed as potential candidates in a leadership race include Home Secretary Shabana Mahmood, Energy Secretary Ed Miliband and backbenchers including former Transport Secretary Louise Haigh.

"He will fight this," one minister said, before making reference to a key by-election in 2021 which Labour lost to the Conservatives, prompting Sir Keir to consider resigning as Labour's leader.

"This is not a Hartlepool moment," they added.

"He is one of only two people alive who have won a general election for Labour. It'd be madness to run against him after 17 months."

In order to trigger a leadership contest against the prime minister, 20% of Labour MPs - currently 81 - would need to nominate a challenger.

Supporters of the prime minister have argued a leadership contest would plunge the party into the chaos associated with the last years of the previous Conservative government.

They are trying to convince their colleagues that a contest could destabilise the international markets too, and would jeopardise the relationship the prime minister has established with President Trump.

Jo White MP, chair of Red Wall Labour backbench group, told the Today programme this was "neither the time or the place" for briefings about a leadership challenge.

"This is a group of people who think they're much cleverer than the rest of us, who spend their time selectively briefing journalists and stirring the pot.

"I want to simply say: we're not having it.

"I'd like to say to No 10, I think they're barking up the wrong tree, briefing against Wes."