Surveying the scale of Labour's disastrous elections performance, the number of Labour MPs saying publicly that Sir Keir Starmer should resign or attach a sell-by date to his premiership had passed 20 by late Friday evening.

Let's see if that is a position that becomes contagious.

There are no shortage of Labour MPs who say it is the prime minister himself who was toxic to many voters.

"There was one issue on the door and it was Keir. If he leads us into a future election we are dead," one Labour MP told the BBC.

Another usually loyal Labour MP, in an area that went heavily Reform in Thursday's poll, told us that the reassuring thing was that voters didn't really hate Labour, but "they did hate Keir".

A senior Labour figure said "everyone in Wales is saying this is all Starmer's fault".

But others do fret about the downsides of a leadership race while the party is in government, and also wonder if it would actually make any difference.

"I am still of the view that anyone who takes over will inherit the same problem - an impatient and almost ungovernable country that wants tax cuts and spending increases on nearly everything," said another Labour MP.

Getty Images Andy Burnham in a grey sweater and white T-shirt arriving for a charity football match Andy Burnham needs to be an MP before he can become leader

Most cabinet ministers have been circling the wagons, taking to the TV studios to reinforce his message that Sir Keir will not be walking away from No 10 and tweeting support for him.

For example, Business Secretary Peter Kyle said: "Reversing these results requires a collective effort, not just blaming the boss."

But while few MPs are entirely "blaming the boss", a significant number think he is part of the problem.

Given the level of dismay and frustration, you might assume there would be even more calls for the PM's removal.

But Labour politics is rarely that straightforward.

Former cabinet minister Louise Haigh told the BBC now was not the time for a messy, internal leadership contest and praised Sir Keir's stance on the Iran war.

But her comments had this sting in the tail.

"The message has been clear from the public," she told the BBC.

"Unless the government delivers urgent and significant change it's clear the PM can not lead us in to the next election."

Her colleague, Sarah Owen, went further and said "unless Keir Starmer delivers tangible change ... he cannot lead us in to another election (locally or nationally)".

Both these MPs are leading figures in the "soft left" Tribune group of MPs - and some of its members want to provide Sir Keir with only temporary support until Greater Manchester mayor Andy Burnham can get back to Westminster and challenge for the leadership.

'Mutinous mood'

What we have seen during the course of the day is a concerted attempt to put pressure on the PM from some on the party's centre-left via interviews and social media for him to announce a timetable for his departure.

At least some of those asking for the prime minister to set a timetable for his departure should be seen as doing so in the context of the ambitions of Burnham.

You can't become Labour leader without being an MP, and Burnham isn't an MP.

A timetable rather than an immediate exit, it is thought, would give time for Burnham's return.

When he tried to become an MP a few months back, he was barred from standing by the party.

Some members of Labour's National Executive Committee have told the BBC they would still be prepared to block his candidacy.

If they do, it's not clear, at this stage, what the Burnham backers' Plan B is.

But as anticipated, a number of MPs are now calling to have this barrier removed.

One of them told the BBC if Burnham was again blocked "the mood in the Parliamentary Labour Party would be mutinous".

Those speaking out publicly are still a small percentage of the 400 plus Labour MPs in the Commons.

But a string of cabinet ministers professing loyalty to the PM on social media is not normal politics because it should go without saying, and it tells you about the anxiety of this moment in Downing Street.

This has, after all, been an extraordinary set of elections. A story of fragmentation, volatility, multi-party politics and records tumbling.

'Hunkering down'

Sometimes it is the details that best illustrate the broader canvas.

The Labour leader of the prime minister's local authority, Camden in north London, lost to the Greens, although Labour hung on to control of the council.

The Conservatives lost to Reform in Kemi Badenoch's backyard of Essex.

And in Kirklees, in West Yorkshire, the local leaders of Westminster's three biggest parties all lost their seats on the same council.

Labour have been winning elections in Wales since before Sir David Attenborough was even born. Until today that is.

Sir Steve Houghton had been the Labour leader of Barnsley Council since Sir John Major was prime minister. Until today that is.

The Scottish National Party have been winning consecutive devolved elections in Scotland since before you could buy an iPhone. And they are still winning.

Labour were thwacked and the Conservatives became a sideshow at the same time.

As things stand, Sir Keir plans to deliver a major speech and unveil a new programme of legislation next week - and even some of his allies acknowledge that how this is received could determine how long he remains in Downing Street. (BBC)

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