Senior government officials have been debating whether to withhold sensitive documents from parliament that reveal Peter Mandelson failed security vetting before becoming US ambassador, the Guardian has learned. Any decision to withhold the papers could breach a parliamentary vote, known as a humble address, which ordered the release of “all papers” relevant to Mandelson’s appointment.
The Guardian previously reported that Mandelson did not receive vetting clearance from security officials, but the Foreign Office overruled that decision to allow him to take up his post. Multiple sources said officials across government are split over whether to release documents detailing these facts to the parliamentary intelligence and security committee (ISC).
The ISC has been tasked with assessing the most sensitive papers, and ministers have assured parliament there will be no block on what the committee sees. However, as of Thursday morning, a decision had not been made about access to Mandelson's UK Security Vetting (UKSV) documents and the Foreign Office override. The Cabinet Office will make the final decision, but sources said officials are divided, with one stating: “There is no consensus.”
Late on Thursday, Downing Street indicated the documents would be released to the committee. A government spokesperson said: “The government is committed to complying with the humble address in full as soon as possible. Any documentation … that requires redaction on the basis of national security or international relations will be provided to the ISC.” Lord Beamish, chair of the ISC, warned that withholding documents would be viewed very dimly by the committee and parliament.



