A powerful parliamentary committee tasked with reviewing files relating to Peter Mandelson’s appointment as US ambassador has revealed that the government is withholding his vetting file despite not having the authority to do so.
In an extraordinary intervention, the intelligence and security committee (ISC) has criticised the government over its handling of the release of Mandelson-related papers and in effect accused ministers failing to comply with parliament’s will.
In February, parliament passed a motion known as a humble address requiring the government to publicly release all papers relevant to Mandelson’s appointment.
The government has repeatedly said it will comply with the motion, which ordered that any documents that could be prejudicial to national security or international relations should first be reviewed by the ISC.
The group of senior MPs and peers have been reviewing the files to decide which, if any, should be redacted or withheld from public release. In a statement on Friday, the ISC said it has completed its work but that it had not been provided all the relevant documents.
“The committee has been told that certain documents are being withheld from the process,” the statement said. It said “the prime example” of documents being withheld was “a vetting file held by UK Security Vetting” (UKSV), the agency that in January 2025 recommended Mandelson’s security clearance should be denied.
The following day, the Foreign Office’s then permanent secretary, Olly Robbins, granted Mandelson his “developed vetting” status anyway, paving the way for him to take up his post in Washington the following month.
Robbins, who has since been sacked by Keir Starmer, has said officials were under pressure from Downing Street to get Mandelson to Washington, but said the pressure did not influence his decision to grant him clearance. Robbins has said he granted clearance without viewing the vetting file, relying instead on an oral briefing from an official who had not seen it either.
In its statement, the committee said it did not believe the terms of the humble address allowed “for any documents to be withheld from parliament”, adding: “While government may believe that there is good reason to withhold certain documents, it does not currently have the authority to so do.”
Starmer’s government is now expected to face intense pressure to explain why it has chosen to withhold the vetting file.
The prime minister’s decision to appoint Mandelson as ambassador to the US in December 2024 has cast a shadow over his premiership and led to calls for his resignation prior to Labour’s poor showing in the local elections.
One of his chief rivals, the former health secretary Wes Streeting, also faces questions over his proximity to Mandelson, whom some have described as his mentor.
The ISC also criticised the government’s approach to redacting documents that have been released. Under the terms of the humble address, documents can be redacted on the grounds of international relations and national security. However, the government has said it is making additional redactions, such as removing the personal data of third parties or information deemed commercially sensitive.
The ISC said it did not believe the humble address provided the government with scope for such redactions, and warned that it believed the redactions were being applied “far too broadly”.
It said the government needed to return to parliament to seek permission to make further redactions. It noted that no body had been commissioned to review the additional redactions made by the government.
In addition to being highly critical of the government’s response to the humble address, the ISC criticised the “extraordinary” amount of government business taking place outside of official systems, such as on WhatsApp, and made what appeared to be a critique of the decision to grant Mandelson clearance against the advice of security officials.
“Lengthy WhatsApp conversations between senior officials and ministers appear now to be the format by which government policy is formulated,” it said. “Perhaps as a result, the lack of an audit trail – in terms of agendas, minutes and records of conversations, in the [Foreign Office] in particular – do not appear to be kept as a matter of practice. This is unacceptable in government.”
In a section headed “failure to adhere to security advice”, the ISC’s statement raised concern that the conclusions of security officials were not acted on. In an apparent reference to UKSV’s advice to the Foreign Office, it said: “Where advice is sought and obtained by those organisations whose job it is to ensure security, for that advice to be overruled to suit some other objective is not acceptable.”
It added: “Proper security concerns cannot be dismissed simply because they are inconvenient.”
Alex Burghart, the shadow chancellor of the duchy of Lancaster, said: “It is outrageous that Labour are trying to withhold documents about the Mandelson-Epstein affair from parliament.
“Throughout this process, Starmer and his ministers have sought to pull the wool over the public and parliament’s eyes. They only started releasing information because the Conservatives forced them to, and even now they are continuing the cover-up.”
The Cabinet Office has been approached for comment.
