Last Friday Andy Burnham left his office to take the 20-minute walk to The Badger, a new gastropub he’d agreed to open in Manchester’s trendy Northern Quarter. Two and a half hours later he finally arrived.

‘It was madness,’ one observer reported. ‘People were stopping him for selfies, wanting to chat, shaking his hand. He was mobbed.’

In the wake of last week’s local election implosion, allies of Keir Starmer grasped hungrily for a few crumbs of comfort. They began briefing journalists the results were so poor there was now no effective route by which the King of the North could engineer a return to Downing Street.

Next week those hopes will be dashed. ‘Andy has the seat lined up,’ an ally confirmed. ‘He’s going to go for it.’

The identity of the constituency is currently a tightly guarded secret. But Burnham’s team are completely confident he will be able to carry it in a subsequent by-election.

‘We’re not idiots,’ one ally explained. ‘We’re not just going to throw him out there. We’ve been conducting our own private polling and we’ve been crunching the national and local polls. He’ll win.’

After months of speculation the strategy that is designed to secure Keir Starmer’s removal from Downing Street has finally been revealed. Within the next seven days Burnham will announce his intention to stand again for Westminster, and the seat that will be the vehicle.

Soon after a raft of members of the Parliamentary Labour Party will publicly call on Keir Starmer to confirm he will not prevent Burnham from standing, or delay the contest. If Starmer agrees, then the immediate challenge to his leadership will be temporarily parked. If he refuses, a delegation of members of the Cabinet will go to him and privately tell him he needs to reverse his decision. If he refuses, then they will seek to remove him from office.

The decision to finally confront the Prime Minister openly is the product of a number of factors. For the past two months Labour backbenchers have been discreetly sounding out colleagues in preparation for a challenge. As one minister told me: ‘I was contacted in April to ask if I’d join in signing a letter calling for Keir to go.’ They claim they politely demurred.

The bulk of the organising was conducted by members of the influential Tribune Group of MPs, whose chair, Louise Haigh, is a close ally of Andy Burnham and Angela Rayner. Their members were primed to act on Haigh’s signal, depending on the outcome of the local elections.

As late as Friday morning, the group were still uncertain about whether to move, given the results were still coming in, and some of the returns appeared to not be quite as catastrophic as initial predictions. But then two things happened.

First, it became clear the results from London would show a major breakthrough for the Greens, mirroring early gains for Reform in the North, and Labour’s extinction in Wales. ‘London is f*****g f****d,’ one despairing backbencher texted me.

Then members of the Cabinet and parliamentary party began to react to Keir Starmer’s bullish statement to the media that despite the disastrous results he had no intention of resigning, and that ‘tough days like this, they don’t weaken my resolve to deliver the change that I promised at the general election, they strengthen my resolve to do so’.

One veteran Cabinet minister called the interview ‘tone deaf and completely counterproductive. It’s like when Tony Blair did his interview saying he was going to go on and on and it created the backlash that forced him out. It had completely the opposite effect to the one No10 intended'.

Another Labour veteran, responding to results in his area, messaged: ‘This guy is an entitled, unprincipled, delusional, useless, selfish lying t****r, surrounded by other entitled, unprincipled, delusional, useless, selfish lying t*****s in No 10.’

In mid-afternoon, Haigh delivered an interview in which she said: ‘What is abundantly clear is that unless the Government delivers significant and urgent change then the Prime Minister cannot lead us into another election.’

That was the signal Labour MPs were waiting for. In the coming hours dozens of backbenchers fanned out across social media calling for Starmer to set out a timetable for his departure.

Incredibly, the carefully choreographed attack caught Downing Street completely by surprise. As one minister observed: ‘Keir’s team have known this moment was coming for months. But when the PLP finally moved they were asleep.’

Starmer’s aides desperately scrambled to get Cabinet ministers to put out their own messages of loyalty. But they found a number of senior ministers were now unwilling to fall into line. Yvette Cooper, Lisa Nandy, Ed Miliband and Shabana Mahmood all tweeted bland statements that pointedly failed to give Starmer their backing. ‘They all knew what signal they were sending,’ a colleague revealed.

Despite the tight co-ordination of the Burnham operation, when he breaks cover next week he will not have a completely clear path towards Downing Street.

Allies of Angela Rayner insist she still harbours her own Prime Ministerial ambitions. But over the past fortnight support for her has begun to fade, with a number of MPs reporting a surprisingly negative reaction to her on the doorsteps over the tax scandal that saw her resign from the Government.

One person who did emerge from Labour’s election drubbing with a smile on his face was Health Secretary Wes Streeting. In Redbridge, which spans his constituency, he helped his local party fend off a challenge from the Tories, Reform and independents to retain control of the council. As one ally said: ‘This shows Wes knows how to win. He can see off the Tories, and he can see off Reform. The Labour vote collapsed in Angela and Andy’s areas. Not in ours.’

Burnham also faces one final obstacle. A badly wounded but embittered Keir Starmer, and his increasingly dysfunctional yet aggressive No 10 machine.

Yesterday the Prime Minister launched yet another – and what most Cabinet ministers and MPs believe will be his final – attempt to relaunch his collapsing premiership. Predictably, it imploded on the launchpad.

To widespread incredulity, the man who had pledged 24 hours earlier to respond to voters’ demands for change unveiled two new Government appointments – Harriet Harman, 75, as his women’s adviser, and Gordon Brown, 75, as his global finance envoy.

One Cabinet minister messaged: ‘I’m waiting for the ghost of Barbara Castle to appear on the steps of Downing Street.’ And a senior backbencher responded: ‘It’s nuts. But more importantly, it’s ineffectual.’

What amazed even normally loyal ministers was that Starmer’s decision to recycle Brown and Harman was not a spontaneous move, but one that had been months in the planning.

In January the PM’s senior aides began to draw up what they called ‘The Plan For May’. This was a strategy for specifically countering what they knew would be a violent political backlash in the wake of a predicted local elections meltdown.

As one minister observed: ‘How can they have seriously thought this was the best response to the results we saw on Friday. We took a beating in the North of England. So he rolls out Gordon, an old Scotsman, and Harriet, the quintessential North London Labour luvvie.’

Another minister warned the move was not just disastrous optics, but would unleash additional chaos within the heart of government. ‘You watch,’ he said. ‘Gordon is going to see this as licence to start dabbling in all sorts of areas of economic policy. Meanwhile Harriet’s going to use it as an excuse to start manipulating all sorts of areas of Government strategy. It’s what she does. She’s brilliant at leveraging her power.’

But the reality is both are unlikely to be in position long enough to do lasting damage. The dam has finally burst. The steady stream of Labour MPs calling for Starmer to set out a timetable for his departure will turn into a flood when MPs reconvene for this week’s King’s Speech. Which in turn will become a tsunami if, as expected, he moves to try to stand in the way of Andy Burnham’s return to Parliament.

In the wake of Friday’s results the Prime Minister vowed: ‘I’m not walking away.’ But as one of his colleagues observed: ‘He says he’s not walking away. The problem is, the voters are.’

They are about to be joined by Keir Starmer’s Cabinet, his ministers and his party.