The note was part of a book the sex offender's accomplice, Ghislaine Maxwell, compiled for his 50th birthday

British Ambassador to the United States Peter Mandelson described Jeffrey Epstein as his "best pal" in a handwritten 10-page letter released by the US House Oversight Committee on Monday.

The message, written for Epstein's 50th birthday in 2003, was included in a bound "birthday book" compiled by Epstein's longtime associate Ghislaine Maxwell. The letter, interspersed with photographs of Mandelson, Epstein, and various settings linked to the financier, portrays Epstein as an "intelligent, sharp-witted" and "mysterious" man who "once upon a time... parachuted" into Mandelson's life.

"You would spend many hours just waiting for him to turn up... And often, no sooner were you used to having him around, you would suddenly be alone again... Leaving you with some 'interesting' friends to entertain instead," one section reads.

"But wherever he is in the world, he remains my best pal! Happy Birthday, Jeffrey. We love you!!" the letter concludes.

The entry featured images ranging from a yellow parachute gliding through the air to snapshots of Mandelson relaxing at some of Epstein's properties.

Asked about the disclosure, a Downing Street spokesperson said Prime Minister Keir Starmer continued to have confidence in Mandelson, who was appointed ambassador in February and has "played a key part" in strengthening trade and investment ties with Washington.

Mandelson, a former Labour cabinet minister and one of the architects of the UK's "New Labour" project, has faced questions over his association with Epstein for years. A spokesperson for Mandelson told the BBC the ambassador "has long been clear that he very much regrets ever having been introduced to Epstein." He previously told the Financial Times that he "wished he had never met him," describing Epstein as a "prolific networker."

Epstein, convicted in 2008 of soliciting a minor for prostitution, was awaiting trial on federal sex-trafficking charges when he died in a Manhattan jail in 2019. Maxwell was convicted in 2021 of conspiring with Epstein to traffic minors for sex and is serving a 20-year sentence.