The UK government released a second batch of around 1,500 pages of documents on June 1, 2026, related to Peter Mandelson's appointment as ambassador to Washington [1, 2, 3].

The files reveal Mandelson was appointed despite warnings about his ties to the late US sex offender Jeffrey Epstein [1, 2, 3]. Mandelson is under police investigation for allegedly leaking government documents to Epstein but faces no accusations of sexual misconduct [1, 2, 3]. He was sacked from the ambassador role in autumn 2025 after disclosures about his friendship with Epstein surfaced [1, 4, 2].

Former Prime Minister Keir Starmer has faced criticism and calls to resign over his judgment in the appointment. Starmer admitted the choice was a mistake but insisted proper procedures were followed and that officials failed to raise vetting concerns with him [1, 2].

The newly released files include internal communications such as WhatsApp messages revealing Labour Party disputes and critiques of Starmer's leadership [4, 3]. In the messages, Mandelson criticized Starmer for lacking "verve" and urged a more risk-taking "Trumpian" style, saying ministers must appear less conventional and more dare-devil [4, 3]. Mandelson also blamed figures like Gordon Brown for undermining Starmer and called Labour MP Wes Streeting "hysterical" over Gaza [4].

Beyond his ambassadorial role, Mandelson actively engaged in political strategy discussions, signaling deep involvement in internal party affairs [4, 3]. He sent a handwritten letter to Foreign Secretary David Lammy promising, "If appointed, you will never regret it" [3].

Starmer’s leadership was further weakened after Labour lost local elections and the Runcorn by-election in May 2025, leading to calls from dozens of Labour lawmakers for him to step down [1, 4, 2].

The first tranche of documents was released in March 2026, showing warnings about Epstein ties and prior resignations [1, 2]. This second release adds significant detail on internal debates and frustrations, with around 1,500 pages made public on June 1 [1, 3].

The UK government has not announced any further document releases, leaving ongoing questions about Mandelson's role and the party's internal challenges.