Peter Mandelson is set to retire from the House of Lords following the latest revelations about his relationship with paedophile Jeffrey Epstein.
His decision to leave the upper chamber was announced by the Lord Speaker, Lord Forsyth, shortly before 3pm. His departure will become effective overnight.
In response to the announcement, a Downing Street spokesperson said: "It is right that Peter Mandelson will no longer be a member of the House of Lords. As the prime minister said this morning, Peter Mandelson let his country down."
Tap here for live coverage as our team combs through the Epstein files
Piling public pressure on Lord Mandelson, Downing Street said that Sir Keir Starmer had told a meeting of his cabinet that he was "appalled by the information that had emerged over the weekend", which included "the alleged passing on of emails of highly sensitive government business" by Lord Mandelson that was "disgraceful".
The prime minister "asked the cabinet secretary to review all available information regarding Mandelson's contacts with Jeffrey Epstein during his time serving as a government minister", Downing Street said.
Furthermore, the Cabinet Office has made a referral to the Metropolitan Police about how Lord Mandelson handled sensitive information when he was in government before the 2010 general election, and Downing Street said it would offer the police its full cooperation with its inquiries.
The Metropolitan Police confirmed that it had received the government's referral, and that an update would be issued in due course.
Former Prime Minister Gordon Brown has also written to Metropolitan Police Commissioner Sir Mark Rowley with "information relevant to his investigation of Lord Mandelson's disclosure of market sensitive and confidential Government information", he said in a statement on Tuesday.
Lord Mandelson has been contacted for comment.
Reacting to Lord Mandelson's decision to step down, Conservative leader Kemi Badenoch wrote on X: "Five months ago, Mandelson was UK ambassador with the full confidence of the PM. Today he is no longer the ambassador, in Labour or a peer.
"The scandal, sleaze, and speed of his downfall only increases the scrutiny on Starmer and [his chief of staff Morgan] McSweeney's decision to send him to Washington."
Although Mandelson will cease to be a member of the House of Lords from midnight, he will not automatically lose his the title of 'Lord', which is separate from membership of the upper chamber. It is understood the government intends to pass pursue legislation to remove his peerage altogether.
The New Labour grandee was awarded a life peerage in 2008, but had been on a leave of absence from 31 January last year following his appointment as UK ambassador to Washington - a post from which he was sacked in September after more details about his links to Epstein emerged.
Stepping down from the upper chamber is the latest development in the dramatic fall from grace for the former cabinet minister, having resigned his Labour membership on Sunday to avoid causing the party "further embarrassment" after documents in newly released files appeared to show he received $75,000 from Epstein.
The latest batch of documents released by the US Department of Justice includes three apparent bank statements detailing three money transfers of $25,000 each from the financier to a Peter Mandelson in 2003 and 2004.
It is unclear whether the payments ever made it into any named accounts.
Lord Mandelson, who was the Labour MP for Hartlepool when the files suggest the payments were made, has denied any record or recollection of the payments - and questioned their authenticity.
He has previously said in a statement: "I want to say loudly and clearly that I was wrong to believe him [Epstein] following his conviction and to continue my association with him afterwards. I apologise unequivocally for doing so to the women and girls who suffered."
After resigning from Labour on Sunday, he said he wanted "to repeat my apology to the women and girls whose voices should have been heard long before now".
Emails have also emerged that appeared to show Lord Mandelson sharing information with Epstein from inside government while he was serving as business secretary and de facto deputy prime minister in Gordon Brown's government.
After the publication of the latest batch of Epstein files at the weekend, Metropolitan Police Commander Ella Marriott said in a statement on Monday: "Following this release and subsequent media reporting, the Met has received a number of reports relating to alleged misconduct in a public office.
"The reports will all be reviewed to determine if they meet the criminal threshold for investigation.
"As with any matter, if new and relevant information is brought to our attention we will assess it, and investigate as appropriate."
He had also appeared in a picture found in the latest Epstein files wearing only his underwear and a T-shirt, which Sky News has confirmed was taken in the paedophile's Paris flat.
A spokesperson for Lord Mandelson previously told Sky News: "No one can say who or where the photo was taken. Lord Mandelson has absolutely no idea or indeed whether it has any connection to Epstein at all."
He said he felt "regretful and sorry" about weekend revelations linking him to "the understandable furore surrounding" Epstein, who took his own life in prison in 2019.
(c) Sky News 2026: Lord Mandelson set to step down from House of Lords after Epstein revelations
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