Are Scottish Labour on the brink of Westminster revolt?

Politically, when someone on your own side is comparing you to dog mess, you know something has gone wrong - especially when they're doing it to try and be supportive.

It has been a difficult few weeks for Sir Keir Starmer and his government, with speculation about a leadership challenge followed by a chaotic run-up to the Budget, a period of damaging leaks and U-turns.

Earlier this week, the Times newspaper said that it had spoken to three Scottish Labour MPs who want to see the prime minister ousted before elections to the Scottish Parliament in May.

In anonymous comments, the MPs reportedly said they fear Labour will be "slaughtered" in those elections, in part thanks to the prime minister's unpopularity.

In response, another Scottish Labour MP told the Daily Record newspaper, using colourful language, that claims of a plot were rubbish.

But in the process they admitted the prime minister was about as popular as something you wouldn't like to step in while out for a walk.

So amid the briefing and counter-briefing, and with Starmer set to visit Scotland less than six months until Scots go to the polls, what really is the mood in the Scottish Labour contingent at Westminster?

Are they on the brink of revolt?

Scottish Labour MPs get together every two weeks or so. They last met on the day of the Budget, so they haven't had the chance to discuss the latest negative press.

"When we do, colleagues are going to be pretty furious," one member of the Scottish group told me.

"It just isn't helpful to go around making out as if we're going to get humped."

While it might have been a point of tension between the Scottish party and UK government in the past, and came in the midst of a chaotic Budget, Scottish Labour MPs are pleased at finally being able to say the two-child benefit cap has been lifted.

But there's no denying there's plenty of unhappiness too.

In the past few weeks I have had Scottish Labour MPs describe the prime minister to me as "terrible" and the conduct of his government, particularly in terms of the chaotic briefings that surrounded last week's budget, as "incompetent" and "mind-blowingly stupid".

That is very different from wanting Starmer out, though.

Culturally and practically, it is difficult for Labour to get rid of its leader - and especially for Scottish Labour MPs.

In the party's long history, Labour MPs have never formally challenged one of their sitting prime ministers, let alone ousted them.

That's quite different from the Conservatives, who have held votes of confidence in two of their last three PMs. Liz Truss didn't last long enough to face one.

And from a Scottish Labour perspective, the timing doesn't make sense right now.

A party insider described talk of a leadership challenge before May to me as "politically inept".

"Do they really want to use up all the time when the focus will finally be on the SNP's record on a leadership contest?" they asked.

Even if they wanted to do it, it would take 80 MPs to trigger a Labour leadership challenge and party rules automatically put the name of the sitting leader on the ballot.

So Starmer would get the chance to defend himself, and his allies have said he'll fight to stay on.

There clearly are Scottish Labour MPs who want to see the end of his leadership.

One told me recently that it was a matter of "when, not if" there would be a leadership challenge.

But how significant the Scottish contingent would be in any plot is questionable.

Of the 37 Scottish Labour MPs, 15 now have front bench jobs, from the Scottish Secretary Douglas Alexander to half-a-dozen parliamentary private secretaries - the bottom rung of the government ladder, but also the first step to a possible ministerial career.

That's not a contract of total loyalty, but it's a sizable down payment.

It all leads to the question: if Scottish Labour MPs aren't pushing to replace Keir Starmer, why not, if their chance of defeating the SNP for the first time in nearly two decades is at stake?

The answer is, because Scottish Labour does not want the prime minister to be a big part of the campaign, even if he is still in office.

Senior party figures say that every moment Anas Sarwar is drawn into responding to Westminster politics and intrigue is a moment when he could be criticising the SNP's record in government.

As one Scottish Labour insider put it to me: "If the election is fought as a referendum on Keir Starmer and the UK government, we lose. If the election is fought as a referendum on the SNP's record of 19 years in government, we win.

"It's that simple."

Starmer will not be visiting Scotland every week as part of the campaign, he won't be in Scottish Labour's party political broadcasts.

Even though these Scottish elections could decide how much of a political future the prime minister has, the campaign simply won't be built around him.

That said, it doesn't mean there is not anxiety about what happens in May.

When you ask Scottish Labour MPs whether they're worried about their party's standing in the polls, the response you get is that they've been underestimated in the past.

Scottish Labour felt like its chances were written off before the Scottish Parliament by-election in Hamilton, Larkhall and Stonehouse in June.

That campaign saw a lot of attention on the Reform Party, which put in one of its best-ever results in Scotland - but still came third.

It was Labour that managed to squeeze out a victory, by just 602 votes.

Party insiders put that victory down to their campaign machinery - the efficiency of their organisation on the ground, the number of volunteers they could mobilise, and the quality of the data they collected on which voters were likely to support them.

All of that is helped by being a party of government at Westminster and the money and resources that brings.

On polling day in Hamilton, Labour says it knocked on 8,000 doors in an impressive get-out-the-vote operation - almost as many as the number of votes it actually won.

But that was a by-election, when the party could concentrate all its resources in one place. What about in May, when there will be 73 constituencies to fight for at Holyrood?

"In a by-election, voters make up their minds on local issues, and on the candidates," one Scottish Labour MP admitted to me.

"At a national election, it's about the national mood music."

The mood music for Labour is a bit discordant just now.