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."
