The British ambassador to the United States Peter Mandelson was fired after a series of emails and other documents that show his onetime support for the late, disgraced financier Jeffrey Epstein.

Mandelson allegedly referred to Epstein as his "best pal" and urged him to "fight for early release" shortly before he was sentenced in 2008 to 18 months in prison for soliciting prostitution from a minor, according to British media reports. A decade later, guards found Epstein dead in his cell at a federal jail in New York City before he could stand trial for sex trafficking charges involving young women and girls. U.S. Department of Justice investigators later concluded that Epstein killed himself.

"The emails show that the depth and extent of Peter Mandelson’s relationship with Jeffrey Epstein is materially different from that known at the time of his appointment," the British foreign office said in a Sept. 11 statement.

"In particular Peter Mandelson’s suggestion that Jeffrey Epstein’s first conviction was wrongful and should be challenged is new information," the statement added: "In light of that, and mindful of the victims of Epstein’s crimes he has been withdrawn as Ambassador with immediate effect."

The revelations of Mandelson's correspondence with Epstein, conducted by email, came to light on Sept. 8. U.S. lawmakers from the House Oversight and Reform Committee released a slew of documents about Epstein that day, including a "birthday book" with messages purported to be from President Donald Trump and former President Bill Clinton, among others. Trump has denied writing the letter.

The Mandelson emails were first published by Britain's Sun newspaper. Mandelson has since admitted in an interview that his association with Epstein went on for "far longer than I should have done." He has also suggested that further "embarrassing" exchanges involving Epstein would emerge.

Mandelson said he "fell for his lies," referring to Epstein .

In one email, from June 2008, according to the Sun, Mandelson wrote to Epstein: "I think the world of you and I feel hopeless and furious about what has happened. I can still barely understand it. It just could not happen in Britain. You have to be incredibly resilient, fight for early release and be philosophical about it."

In another, from February 2008, also reported by Bloomberg, Mandelson wrote to Epstein: "Reminder. You are fighting back so you need strategy, strategy, strategy. Remember the Art of War."

Mandelson represents British Prime Minister Keir Starmer's Labour Party. The opposition Conservative Party leader Kemi Badenoch called on Sept. 10 for Mandelson to resign. The Liberal Democrats, another opposition party, have called for a formal investigation into what exactly what Starmer knew about Mandelson's contacts and correspondence with Epstein before he appointed him U.S. ambassador in December last year.

Mandelson is a veteran British politician who also served in former prime minister Tony Blair's Labour government. He is viewed in the U.K. as having played an influential role in helping his country secure a trade deal with the U.S. The disclosures about his emails to Epstein come just days before Trump is due to travel to the United Kingdom for a state visit. Mandelson has said he has not discussed the issue of Epstein with Trump.

This article originally appeared on USA TODAY: UK ambassador Peter Mandelson fired over Jeffrey Epstein ties

Reporting by Kim Hjelmgaard, USA TODAY / USA TODAY

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