The Metropolitan Police has launched a criminal investigation into Peter Mandelson over allegations of misconduct in public office.

It comes after the former Labour minister and US ambassador was accused of passing market-sensitive government information to US financier and convicted sex offender Jeffrey Epstein.

Emails released by the US Department of Justice (DoJ) appear to show Lord Mandelson forwarded information to Epstein when he was business secretary under former Prime Minister Gordon Brown in 2009.

Lord Mandelson did not respond to requests for comment but the BBC understands his position is that he has not acted in any way criminally and that he was not motivated by financial gain.

A government spokesperson said: "The government stands ready to provide whatever support and assistance the police need."

Lord Mandelson - who was sacked as the UK's ambassador to the US last year - has told parliamentary authorities he intends to resign from the House of Lords on Wednesday.

On Monday, the Scottish National Party and Reform UK said they had reported the peer to Scotland Yard and on Tuesday, the UK government said it had referred material to the police after assessing emails Lord Mandelson appeared to have sent to Epstein while he was business secretary.

A No 10 spokesperson said an "initial review" of the documents had found they contained "likely market sensitive information surrounding the 2008 financial crash".

Brown - who was prime minister between 2007 and 2010 - said he had written to Metropolitan Police Commissioner Sir Mark Rowley with "relevant" information relating to Lord Mandelson's apparent correspondence with Epstein.

Brown said he had shared with police a letter he had sent in September asking the cabinet secretary to "investigate the veracity of information contained in the Epstein papers regarding the sale of assets arising from the banking collapse and communications about them between Lord Mandelson and Mr Epstein".

Brown said the alleged correspondence was an "inexcusable and unpatriotic act at a time when the whole government and country were attempting to address the global financial crisis".

In a statement, Met Police Commander Ella Marriott said: "Following the further release of millions of court documents in relation to Jeffrey Epstein by the United States Department of Justice, the Met received a number of reports into alleged misconduct in public office including a referral from the UK government.

"I can confirm that the Metropolitan Police has now launched an investigation into a 72-year-old man, a former government minister, for misconduct in public office offences.

"The Met will continue to assess all relevant information brought to our attention as part of this investigation and won't be commenting any further at this time."

Over the weekend, Lord Mandelson reiterated his regret about his continued association with Epstein, apologising "unequivocally to the women and the girls who suffered".

Although Lord Mandelson will no longer be a member of the Lords once he has stepped down, he will retain his life peerage, a title which can only be removed by an Act of Parliament.

A No 10 spokesperson said the government was drafting legislation that would ensure Lord Mandelson's peerage could be removed "as quickly as possible".

Prime Minister Sir Keir Starmer began his Tuesday morning Cabinet meeting by saying Lord Mandelson had "let his country down" and that the alleged passing on of emails was "disgraceful", according to Downing Street.

Sir Keir also told his senior ministers he was "not reassured that the totality of the information had yet emerged".

The apparent emails between Lord Mandelson and Epstein were part of a huge release of documents by the DoJ on Friday.

Emails released in the files from 2008 appear to show Lord Mandelson - who was then business secretary - discussing the government's plans for a one-off tax on bankers' bonuses with Epstein.

Other emails published in the tranche of documents from the DoJ appear to suggest:

Lord Mandelson gave advance notice to Epstein of a €500bn bailout from the EU to save the Euro
Epstein made $75,000 in payments to Lord Mandelson in three separate $25,000 transactions in 2003 and 2004. Lord Mandleson has said he has no record or recollection of the payments
Epstein sent £10,000 to Lord Mandelson's partner Reinaldo Avila da Silva in 2009.

Lord Mandelson said he was resigning his Labour membership in a statement released on Sunday.

He also said he believed allegations that Epstein had made financial payments to him 20 years ago were false.

Lord Mandelson's friendship with Epstein was known when he was appointed as US ambassador in 2024, but he was sacked last year when embarrassing details about their association were released.

No 10 is now facing questions about its vetting process, and how much it knew about the friendship when it decided to make the appointment.

The government will confirm on Wednesday that it is willing to publish information relating to its decision to appoint Lord Mandelson as the UK's ambassador to the US.

The Conservatives are planning to use a parliamentary technique known as a humble address to attempt to compel ministers to release the information.

Humble addresses, if agreed, are understood to be binding on the House.

The Tories have devoted considerable time to ensure the wording makes it very difficult for Labour MPs to vote against it.

But the government has suggested an amendment to it, which would promise to release the information "except papers prejudicial to UK national security or international relations".

It isn't expected any information would be released immediately.

Conservative leader Kemi Badenoch said the prime minister had "a lot of questions to answer" about the appointment of Lord Mandelson as US ambassador, adding Sir Keir "should not try and distract anyone by talking about removing peerages or investigations".

Conservative Party chairman Kevin Hollinrake told BBC Radio 4's Today programme that the prime minister should "make a clean breast of everything" with full disclosure of information about Lord Mandelson, saying it would be "wrong if anything is held back".

Liberal Democrat leader Sir Ed Davey has called for a public inquiry into how Epstein had been able to "gain access to the heart of the British political establishment". (BBC)

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