Sept. 11 (UPI) -- British Prime Minister Keir Starmer on Thursday fired U.S. Ambassador Peter Mandelson amid revelations of a close friendship with convicted U.S. sex offender Jeffrey Epstein.

The Foreign Office said in a statement that the 71-year-old had been dismissed after communications emerged showing the "depth and extent" of his relationship with Epstein was "materially different from that known at the time of his appointment."

"In light of that, and mindful of the victims of Epstein's crimes, he has been withdrawn as Ambassador with immediate effect."

The firing came after Conservative opposition and politicians across the political spectrum called for Mandelson to be recalled to London and replaced after a House committee released records from Epstein's estate in which Mandelson referred to Epstein as his "best pal."

There was uproar in the House of Commons on Wednesday as Starmer insisted Mandelson continued to retain his backing, was "playing an important role" in U.K.-U.S. relations and that "full due process" was undertaken before his appointment in December.