Yvette Cooper brands Peter Mandelson files 'unedifying' as she claims he should 'never have been appointed US ambassador'

This morning on GB News, Paymaster General Nick Thomas-Symonds admitted the messages were "embarrassing" and added they were "meant for private consumption".

Sir Keir's leadership capabilities were repeatedly questioned in the private messages, with Lord Mandelson describing the Prime Minister as "consistently going for direction B".

When questioned over the former Cabinet minister's description of Prime Minister’s working cycle as "advance/buckle/advance/buckle", Ms Cooper admitted that the peer should "never have been appointed" to the role.

She added: "Of course, there's been a lot of transparency now about messages being released. That’s always an unedifying process but right to be transparent.

"We mustn’t forget two things, first is that in the end this whole thing started about Epstein’s abuse of young women and girls, and sometimes the conversation gets pulled away from that.

"And, secondly, I think the whole Government is getting on with the most important issues that affect our country and that’s exactly why I’m here in China having these important discussions about international security."

The Foreign Secretary also dodged a grilling on whether she would describe Sir Keir as a "strong and effective leader" while on a trip to Beijing.

She refused to give a straight answer, simply saying: "I'm in China pursuing issues around international security which follows on from the Prime Minister’s visit here to China with President Xi earlier this year."

Amid more than 1,000 pages of damning documents, records of WhatsApp correspondence between Lord Mandelson and Work and Pensions Secretary Pat McFadden exposed the minister's disgruntlement with party colleagues.

Back in May 2025, Mr McFadden privately divulged speculation about Sir Keir's leadership strength during tumultuous times for Labour.

Following the Government's first set of poor local election results, the minister wrote: "Lot of manoeuvring here this week. Angela (Rayner), Gordon (Brown). Doesn’t feel good for Keir."

But he also took aim at his more junior Whitehall colleagues, many of whom he asserted were "asking the wrong questions".

"Every meeting I have is 'who can we tax in order to pay benefits to others'," the top minister complained.

Lord Mandelson, in messages with a number of leading Labour ministers, criticised Sir Keir's "lack of verve" and the Chancellor's "growth mission".

He wrote: "I felt when Rachel was here that she was on a growth mission but without an argument about where the growth will come from or how."

The peer sounded the alarm over Ms Reeves' potentially considering a "huge bank levy" to afford winter fuel payments and the end to the two-child benefit camp.

"It would be tantamount to abandoning long term growth for short term (parliamentary Labour party) management," he warned."

Since Labour lost swathes of support across England and Scotland as well as its 27-year-long grip on the Senedd at this year's round of Local Elections, close to 100 Labour MPs have demanded the Prime Minister step down from his role.