chris mason
political editor

Sir Keir Starmer is a prime minister who is wary of superlatives and who naturally tends to show little emotion in public.

This is what made the Prime Minister’s questions today so extraordinary. There was obvious anger in Starmer’s tone, a barrage of superlatives of disgust and betrayal.

he “I lied, lied, and lied again.” the Prime Minister insisted.

It said there had been “a series of deceptions” and Mr Mandelson’s actions were “beyond outrageous”, adding that Mr Mandelson had betrayed his party, parliament and country.

While the government is hell-bent on burying Mr. Mandelson under a pile of blame visible from space, the feelings of anger and betrayal are real. Over the past few days, I’ve heard from Labor Party officials in person and over the phone about this.

But the question remains – and will no doubt be repeated many times in the Chamber this afternoon – what and when did the prime minister know about Lord Mandelson’s conduct, and what questions were and were not asked before his appointment to Washington.

That’s why Mr Mandelson’s actions remain so important to the prime minister’s reputation.

It could still be several weeks or more before some of the documents the government is currently releasing about the circumstances that led to Lord Mandelson’s appointment as ambassador to Washington are made public.