What was the vetting process for Mandelson's appointment as US ambassador?

Documents relating to Lord Mandelson's appointment as the UK's ambassador to the US are due to be released, following pressure from MPs.

Prime Minister Sir Keir Starmer has acknowledged the vetting process included discussion of Lord Mandelson's continued relationship with Jeffrey Epstein after he was convicted.

However, he has accused Lord Mandelson of lying throughout the process and misrepresenting the extent of their relationship.

The BBC understands Mandelson's view is that he answered questions about his relationship with Epstein in the vetting process accurately.

It was essentially a two-stage process: an initial due diligence check prior to his appointment, followed by security vetting. So how did it work?

The due diligence check was carried out by a team at the Cabinet Office on behalf of Downing Street, as the prime minister was responsible for the appointment.

The point of this check is to identify reputational risks or potential conflicts of interests that may need to be considered during the hiring process.

Sir Chris Wormald, the UK's top civil servant, has previously confirmed to MPs that this was largely based on public information, such as media reports.

At the time, it was public knowledge that the peer had maintained his relationship with Epstein after his conviction for soliciting sex from a minor in 2008.

In 2023, the Financial Times reported emails suggesting he stayed at Epstein's Manhattan mansion in 2009, while the financier was in jail.

The only non-public information that featured, Sir Chris added, were records of a meeting Lord Mandelson facilitated between Epstein and Sir Tony Blair that have since been disclosed by the National Archives.

This appears to be a reference to a meeting in Downing Street in 2002, six years before Epstein's conviction.

Lord Mandelson's file included information about his previous roles inside and outside government, and his "professional and financial relationships".

His prior relationship with Epstein was listed as a reputational risk, Sir Chris added, alongside his previous two resignations as a minister during the last Labour government.

After reviewing the file, No 10 sources said Sir Keir asked Lord Mandelson to address three specific questions, which were sent to him via email by the prime minister's chief of staff, Morgan McSweeney.

These questions were: why has he continued contact with Epstein after he was convicted? Why was he reported to have stayed in one of Epstein's homes while the financier was in prison? And was he associated with a charity founded by Epstein associate Ghislaine Maxwell that the financier had backed?

At the time, his answers were considered sufficient for him to be appointed to the role, meaning he then underwent security vetting. No 10 will no doubt face pressure to release them as part of the disclosure process approved by MPs.

In addition to providing information about his private interests, Lord Mandelson would have undergone security vetting before taking up the role.

The Foreign Office, which is responsible for Britain's overseas embassies, says all ambassadors are required to go through developed vetting (DV), the most intrusive process required to access the most secret government information.

Security vetting is carried out by United Kingdom Security Vetting (UKSV), a specialist agency within the Cabinet Office.

The process is designed to make sure those being vetted are unlikely to abuse their access to secret material, or be subject to blackmail or bribery.

According to government guidance, those undergoing DV are required to fill out various questionnaires including information about their personal finances, internet use, medical conditions, and email addresses they hold.

Several checks are carried out, including on candidates' credit history and to check if they have any criminal records.

Those being vetted also have to undertake an interview with a specially trained vetting officer, which can cover areas including candidates' health, friendships, family and sexual history.

The UKSV decides whether or not to award security clearance, and can attach mitigations, such as being prevented from seeing certain information.

The results of this vetting are kept within a tight circle and only the vetting agency and the security team can see the contents. Ministers, including the prime minister, never see the details.

Ultimately, Lord Mandelson was announced as the UK's ambassador to the US in December 2024.

However, after less than a year in the role, he was sacked last September following the emergence of new emails revealing supportive messages he sent to Epstein after he pleaded guilty to sex offences.

The government said the depth of their relationship was not known when he was appointed.

However, the PM is now facing questions over whether the information in the public domain was enough to raise alarm bells.

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