The UK government is expected to publish a second and potentially extensive batch of documents concerning the appointment of Lord Peter Mandelson as the UK’s ambassador to the United States.According to sources involved in the process, the documents will be released when Parliament returns from recess on Monday.

The publication follows a parliamentary vote in February that compelled the government to disclose all relevant papers through a Humble Address procedure.Initially, ministers resisted the release, citing concerns about national security and diplomatic relations.A compromise was eventually reached whereby sensitive material would first be reviewed by the Intelligence and Security Committee before publication.

The first tranche of documents, released in March, revealed that Prime Minister Sir Keir Starmer had been warned that Mandelson’s past association with convicted sex offender Jeffrey Epstein posed a reputational risk.The papers also showed that national security adviser Jonathan Powell considered the appointment process unusually rushed.Starmer had appointed Mandelson to the Washington role in December 2024, praising his experience and suitability for the position.However, Mandelson was later dismissed after additional details emerged regarding his long-standing relationship with Epstein.

Mandelson has acknowledged that the friendship was a serious error in judgement but has maintained that he had no knowledge of Epstein’s criminal activities.

The forthcoming release is expected to include all relevant documents except those withheld at the request of the Metropolitan Police during an ongoing investigation.Certain sections may also be redacted to protect national security interests, international relations, or the identities of junior civil servants.The affair has generated significant political criticism, with MPs questioning the judgement behind Mandelson’s appointment.

Mandelson is currently under criminal investigation over allegations of misconduct in public office, although he denies any criminal wrongdoing and states that he is fully cooperating with investigators.