Cabinet Office to release second tranche of Mandelson files

The UK Cabinet Office is scheduled to publish the second tranche of documents concerning Peter Mandelson’s appointment as Ambassador to the United States, following a request via a humble address in the House of Commons. This release includes over 1,000 pages of emails and WhatsApp messages involving ministers and officials. However, it excludes a nine-page UK Security Vetting (UKSV) summary that recommended denying Mandelson clearance due to concerns regarding his associations with figures in China, Russia, and Israel. The exclusion follows a request by the Metropolitan Police. Questions have been raised about the clearance process, particularly the lack of written records for security mitigations agreed upon by senior officials Olly Robbins and Ian Collard, who made their decision in late January 2025 based on oral briefings rather than the summary document.

Senior Foreign Office officials Olly Robbins and Ian Collard made the clearance decision for Peter Mandelson in late January 2025 based on oral briefings. The nine-page UK Security Vetting summary document was reviewed seven months later, approximately in August 2025. On Monday, the UK Cabinet Office is set to release the second tranche of documents, including over 1,000 pages of communications, triggered by a House of Commons humble address.

The release of exchanges from Mandelson’s time in Washington could include criticism of the prime minister and awkward WhatsApp messages from ministers “trying to impress” the now former US ambassador. These could include group messages involving the former health secretary Wes Streeting, who has tried to distance himself from Mandelson. Government insiders have suggested there will also be messages revealing that Mandelson gave unsolicited advice to ministers on policy areas outside his diplomatic brief.

The documents to be released are understood not to include a nine-page summary document compiled by UK Security Vetting (UKSV). The Guardian disclosed last week that Mandelson’s associations with senior figures in China, Russia and Israel had been among the concerns raised by UKSV when it concluded he should be denied clearance – and these were all contained in the summary document. However, reports on Sunday suggested officials were no longer planning to release it after the Metropolitan police requested some documents not be made public.

Multiple sources have told the Guardian the documents contain no written record of what Mandelson and top security officials agreed would be necessary for him to receive security clearance for the job. Senior Foreign Office officials have told MPs that he agreed to take certain steps to allay concerns, but the lack of any written agreement casts doubt on those assurances. Some steps appear to have been taken to address commercial conflicts of interest caused by Mandelson’s stake in Global Counsel, the lobbying firm he co-founded. These management actions, however, were separate to security mitigations.

Olly Robbins, the senior government official sacked for his role in appointing the former Labour minister after UKSV had recommended clearance be denied, told MPs the vetting body had “considered Mandelson a borderline case” and was only “leaning towards” recommending that his clearance should be denied. However, there have been no documents published so far that support the “borderline” claim – and the term has not been used by anyone else who has seen the UKSV documents. In fact, a template of the UKSV decision document suggests the exact opposite.

One prevailing mystery has been why Robbins and Ian Collard, the Foreign Office’s security chief, made their decision in late January 2025 without reviewing the summary document, doing so on the basis only of oral briefings about its contents. It was seven months later, when Mandelson was withdrawn from Washington, that they decided to review the summary document. Robbins told MPs that queries had been made on his behalf about whether he could see the document – and that the Cabinet Office had said he needed a national security justification. However, the Cabinet Office’s top civil servant has said another request was made by the Foreign Office’s security team, which led to the summary document being handed over. Notes were apparently then taken of its contents by the security chief. It is unclear what triggered that action, and what the contents of the note were.