Gordon Brown is demanding the Metropolitan Police “urgently” investigates Andrew Mountbatten-Windsor for sex trafficking.
The former prime minister has written to Scotland Yard urging detectives to re-examine a decision not to investigate the ex-Duke of York, 65, over allegations Jeffrey Epstein transported exploited women to sleep with him in London.
US congressman Ted Lieu claimed a woman pictured under Andrew on all fours at the paedophile financier’s New York mansion was a sex trafficking victim.
Thames Valley Police is assessing claims Andrew leaked confidential material to Epstein while he was trade envoy. The former prince denies any wrongdoing.
Brown had spent the last week examining the recent Epstein files released by the US Department of Justice.
He said: “What I discovered about the abuse of women by male predators and their enablers - and Britain’s as yet unacknowledged role - has shocked me to the core. It demands an in-depth police investigation, and is by far the biggest scandal of all.”
In December, a BBC investigation found 87 flights - dubbed the “Lolita Express” - linked to the convicted sex offender had arrived or departed from UK airports between the early 1990s and 2018, some with British women on board who say they were abused by Epstein.
Writing in The New Statesman, Mr Brown said he was shocked to read emails about Epstein boasting he could use Stansted Airport to fly in girls from Latvia, Lithuania and Russia.

He wrote: “I have been told privately that the investigations related to Andrew did not properly check vital evidence of flights. I have asked the police to look at this as part of the new inquiry.
“It seems the authorities never knew what was happening,” he said, adding that the names of passengers were often withheld.
“In short, British authorities had little or no idea who was being trafficked through our country, and for whom other than Epstein.”
He went on: “I have asked the Met urgently to re-examine their decision-making in their investigation and the subsequent reviews.
“Even women who have been mentioned in the files, whose names should have been requested months ago from the US Department of Justice, do not appear to have been contacted by British investigators.”
The Sun reports a succession of females were invited to see Andrew at Buckingham Palace.
One source said: “He would phone the duty office and always say the same thing - ‘Mrs Windsor will be arriving shortly, please let her in and show her up’.
“This was always via one of the out-of-sight staff entrances.
“It was so frequent that they used to just roll their eyes and say ‘yes sir’. It went on for years. The royal protection officers hated being assigned Andrew as he was so unpleasant and dismissive.”
The Epstein scandal has engulfed Westminster and the monarchy since the US authorities published millions of documents.
The Yard is investigating Lord Peter Mandelson over allegations of misconduct in public office amid claims he sent market-sensitive information to Epstein while he was business secretary during the 2008 financial crisis.
Officers are sifting through boxes of evidence removed during searches of the peer’s house near Regent’s Park, central London, and a property in Wiltshire last week Friday. Lord Mandelson, 72, has not been arrested.
The Standard approached the Met for comment.