Chris Mason: Starmer can ill afford any more days like these

The prime minister is furious, and more furious with Lord Mandelson than he has been with anyone else for many years, I'm told.

The mood among many Labour MPs is darkening, even blackening.

There is a recurring sense from many of being on the wrong end of indefensible positions far, far too often, of which this latest row about Lord Mandelson is just the latest case study.

The prime minister weathered arguably his most difficult day in office yet on Wednesday, with plenty on his own side privately pondering how sustainable it is for things to carry on as they are, the government seemingly incapable of getting on the front foot.

Bluntly, Sir Keir Starmer can ill afford any more days like these.

Lord Mandelson, for his part, is offering no public comment, having frequently been offered the opportunity to do so.

The argument, depending on who you listen to, goes one of two ways.

There are those not only livid with Lord Mandelson, but livid at the collateral damage being done to the prime minister.

"Keir Starmer and Morgan McSweeney have massive faults, but they acted in good faith and don't deserve to lose their jobs over this," one insider tells me, in reference to the prime minister and his chief of staff.

Another stresses that the prime minister knew nothing more about Lord Mandelson's friendship with Jeffrey Epstein at the time he was appointed the UK's ambassador to the United States than was known publicly.

I wouldn't be surprised if this is the line we hear from ministers and the prime minister himself in the coming days.

But for others this is exactly the point: surely what was known publicly about their friendship at the time was enough to realise it would be a terrible idea to send him to Washington, goes their argument, particularly given even then there was the prospect of files like these being published at some point?

In other words, this was a time bomb waiting to go off.

For those loyal to the prime minister, and Sir Keir himself, the strategy now is to attempt to bury Lord Mandelson under a Himalayan heap of opprobrium.

They are not missing a single opportunity to double down on this.

A Downing Street spokesman said Lord Mandelson "presented Jeffrey Epstein as someone he barely knew".

I have heard similar from elsewhere in Whitehall an account that substantiates this and there is hope from Sir Keir's allies that in time the disclosure of the vetting process will confirm it for all to see.

But I also hear, incidentally, that the vetting process was "rushed" and "slapdash".

And there is every prospect much of this material may not see the light of day for ages, given the Metropolitan Police are nervy about anything being published that could prejudice any potential future legal proceedings following their investigation into Lord Mandelson.

In recent days ministers have had to accelerate their planned responses to this scandal for fear of being seen to be dawdling or ducking a perceived need for a duty of candour - and it has happened again.

And it happened via the politically significant public intervention of the former deputy prime minister Angela Rayner among others, suggesting that leaving the decision about what documents about Mandelson's appointment are disclosed to civil servants was inadequate and MPs and peers on the cross party Intelligence and Security Committee should decide instead.

Yes, the former deputy prime minister nudging, or shunting the government into a position it had not intended to adopt, because she and plenty of other Labour MPs were not willing to accept Downing Street's initial position.

It tells you rather a lot about the power dynamics between the government and its backbenches - and it is not one to inspire confidence if you are sitting at the centre of government.

The prime minister will now try, again, to seize the agenda. It has been a recurring theme of these opening weeks of 2026 that whenever he has tried to do so, events have knocked him off course.

There has been Venezuela, Greenland and now Lord Mandelson.

In other words some events beyond his control, others within it.

He will give a speech later about his first principles - his values and his patriotism.

"I love this country. It is the greatest country in the world. The progress and prosperity I've seen throughout my life. The journey I've been on, personally from a working-class background to this, I owe everything to this country and its values. I've spent most of my professional life serving them," he will say.

The thing is, and he knows it, nearly every question afterwards will be about his judgement and Lord Mandelson.

Lord Mandelson is understood to insist he has not acted criminally, did not act for personal gain and will cooperate with the police.

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