By noon yesterday, Downing Street spin doctors were becoming increasingly confident they had seen off Wes Streeting and Andy Burnham. ‘Wes has bottled it,’ journalists were told, ‘and Andy can’t get a seat.’

Five hours later, that aggressive, hubristic briefing had blown up in their faces. Streeting had resigned from the Cabinet and put rocket boosters under the anti-Starmer insurgency. And Makerfield MP Josh Simons had confirmed he is standing down to give Burnham a potential path back to the Commons.

Streeting was in his Westminster office, taking calls from Cabinet ministers who had been dispatched by Keir Starmer to try to prevent him from resigning, when he turned to his team of advisers. ‘Right, I’ve made up my mind,’ he said. ‘Let me write my letter.’

His resignation missive to the Prime Minister was an elegant but brutal evisceration of Starmer’s record. ‘Where we need vision, we have a vacuum,’ he wrote.

‘Where we need direction, we have drift. This was underscored by your speech on Monday. Leaders take responsibility, but too often that has meant other people falling on their swords.’

But the key passage of the letter was more prosaic. A contest to replace Sir Keir was now required, he said, one that ‘needs to be broad, and it needs the best possible field of candidates’.

A couple of minutes after the letter was published, I received a call from a minister. ‘Wes and Andy have done a deal,’ they told me. ‘They’ve both agreed to a long timetable for a contest that gives Andy the time and space to come back. It’s over.’

Keir Starmer’s last, desperate resort to cling on to power was to drive a wedge between those rebels who were demanding a long contest – facilitating Burnham’s return – and those who wanted a much shorter contest, favouring Streeting.

But by taunting and goading the two rival camps, No10 unwittingly drove them together.

As a Cabinet minister told me: ‘We’ve now got a situation where the main leadership rivals are united behind a timetable for Starmer to go, two-thirds of the Cabinet are behind it, half the parliamentary party are behind it and so are all of the affiliated trade unions. He’s f***** himself.’ A couple of hours after Streeting’s resignation, Simons confirmed he was relinquishing his seat for Burnham to contest.

Advisers to both Streeting and Burnham deny any official pact was arranged between them over a timetable.

But a source confirmed they had spoken to one another on Friday, although ostensibly to discuss the hantavirus outbreak and the fact that some of the patients were being treated in the North West.

‘They didn’t speak much about politics,’ I was told cryptically.

Some ministers believe there was even more sophisticated – and surreptitious – choreography at play behind the staggered announcements.

One Cabinet minister pointed to the close relationship between Josh Simons and Home Secretary Shabana Mahmood, who split from Starmer on Monday by telling him in private he should set out a timetable for his departure.

According to one Cabinet colleague: ‘Josh and Shabana are joined at the hip. When she was made Home Secretary, she demanded that he was promoted to her department. When Simons was informed by the Labour chief whip that he was going to be sent to the Cabinet Office instead, he reportedly replied, “That’s not the plan. Speak to Shabana”, and put the phone down.’

Starmer’s allies insist Streeting and Burnham are simply trying to cover for the fact that the former Health Secretary failed to secure the 81 names needed to trigger an immediate leadership challenge.

‘This is all b******t,’ said one. ‘Wes didn’t have the numbers and was forced to retreat. He’s been completely humiliated.’

Streeting’s allies deny that.

They insist the primary reason for aligning with Burnham was the realisation that anyone who secured the leadership via a contest that did not include the self-styled ‘King of the North’ would have a tainted mandate.

‘Wes recognised that even if he did win, he wouldn’t have proper legitimacy if Andy hadn’t been allowed to run’, they conceded. ‘It would have ended up splitting the party.’

Streeting’s decision to step down sent a shockwave through Downing Street.

But just as Starmer and his aides were trying to wargame how to respond to the Health Secretary’s resignation, rumours abounded that Burnham was close to securing a seat.

A Cabinet minister contacted me to say: ‘[No10] have started ringing round, trying to find out who’s preparing to step down for him. They want to kill the whole thing off.’

When I contacted a Burnham supporter to relay the conversation, he hit back: ‘I’m sure they are. But we’re solid.’

They were. As with their attempt to marginalise Streeting, Downing Street’s attempt to intercede in Burnham’s plot ended in abject failure.

As one minister observed: ‘They’ve completely lost control in there. Some of their briefing against Wes over the past few days has been disgusting.

‘One of Keir’s allies was telling journalists: “Do you know that Peter [Mandelson] paid for Wes’s wedding?” Wes isn’t even married.’

Some ministers had told me the collapse of authority in No10 was a result of the vacuum created by the recent departure of Starmer’s powerful chief of staff Morgan McSweeney. But according to ministers, he has been brought back into the fold to organise Starmer’s final defence.

‘Morgan’s spent the day trying to coordinate the fightback,’ one told me. ‘He’s been dialling in on their strategy calls.’

Another told me: ‘That’s why Keir’s been digging in. He basically recognises it’s all over. But Morgan is telling him to keep fighting.’

But by driving Starmer’s enemies into an unlikely alliance, that fight now appears to be nearing its end.

As one Cabinet minister, who until now has been solidly loyal to the Prime Minister told me: ‘Wes had to fold. He didn’t have the numbers, and he didn’t have a path to No10. But this can’t go on.

‘Over the next few days people are going to have a talk with Keir. This isn’t sustainable. We’re not able to govern.’

My understanding is that some of those tricky conversations are now under way. On Wednesday, another raft of Cabinet ministers contacted No10 to say that Starmer needed to recognise his position was untenable. Two more ministers delivered the same message yesterday.

As another minister told me: ‘If we haven’t seen a podium standing in Downing Street by this time next week, I’ll be amazed.’

On Wednesday, Keir Starmer decided to throw down the gauntlet to Wes Streeting and Andy Burnham. Streeting would not dare resign, he predicted. Burnham would never find a seat, he boasted.

He was wrong. The streetfighter from Stepney and the King of the North have accepted the challenge. It is now a fight to the death.

One that, thanks to his own arrogance and hubris, Keir Starmer is now certain to lose.