The EU's anti-fraud office has begun a formal investigation into Lord Peter Mandelson, who was sacked as UK ambassador to the US over his ties to late sex offender Jeffrey Epstein.
Lord Mandelson served as European trade commissioner from 2004 to 2008. The European Commission asked the European Anti-Fraud Office (Olaf) two months ago to look into allegations of misconduct during that four-year period.
Olaf confirmed on Friday that it had recently had "sufficient information" to launch an investigation, but said it was too early to say whether or not it involved allegations of fraud.
After Lord Mandelson left Brussels, he became UK business secretary until 2010.
Olaf is expected to look at exchanges with Epstein from Lord Mandelson's time as EU commissioner. It has confirmed its mandate covers all four years, and is limited to staff and members of EU institutions.
However, emails to Epstein have also surfaced surrounding the eurozone crisis in 2010. Among the allegations are that Lord Mandelson gave Epstein advance notice of an impending €500bn (£434bn) bailout, when EU governments decided to do "whatever it takes" to stop Greece's financial crisis spreading to other countries in the eurozone.
Lord Mandelson has not commented on the allegations but the BBC understands he has denied acting in any criminal manner and was not motivated by financial gain.
The anti-fraud office said it had no jurisdiction to prosecute and made clear that "if there is a criminal element we will pass it to the European Prosecutor's Office".
Olaf's role is to investigate allegations of fraud that relate to the EU's budget, as well as corruption and serious misconduct within EU institutions.
It can recommend sanctions against someone under investigation, but the decision has to be taken by relevant EU authorities. Among the recommendations possible are judicial, financial, administrative and disciplinary, so that could include revoking the former commissioner's pension.
Olaf told the BBC that any documents would now be analysed and that "IT forensics" would be done, insofar as they were available after so many years. It could not confirm whether further allegations had come to light since February.
Earlier this year, email exchanges between Lord Mandelson and Epstein emerged from that period, prompting the UK's Metropolitan Police to launch a criminal investigation into suggestions that he had passed on market-sensitive information during his time as business secretary in 2009.
Lord Mandelson was sacked as UK ambassador to the US in September 2025 as the extent of his friendship with Jeffrey Epstein became clear.
The scandal surrounding the peer's ties to Epstein continue to reverberate through UK politics, and this week the former top civil servant at the Foreign Office, Sir Olly Robbins, said he had been pressured to rush through Lord Mandelson's appointment as ambassador to the US.
