The Foreign Office chief who lost his job over the Peter Mandelson vetting scandal is in discussions with Andy Burnham’s team about taking on a security-related role under the likely new prime minister, the Guardian understands.

Olly Robbins has had “early exploratory talks” with senior advisers to the newly elected Makerfield MP over a post in his putative Downing Street operation, and insiders suggested he could be appointed national security adviser.

It would mark a dramatic and controversial return by Robbins to the top of government less than three months after he was sacked by Keir Starmer following the Guardian’s disclosure that he had overturned a recommendation from UK Security Vetting to deny clearance for Mandelson.

The disclosure is likely to ring alarm bells with senior Labour figures, including some of those currently in No 10, after he lost the confidence of Starmer and Yvette Cooper, the foreign secretary, due to his handling of the vetting of Mandelson, who was sacked over the extent of his links to the convicted child sex offender Jeffrey Epstein.

Questions remain about the defence Robbins mounted, both of himself and the system through which the national security establishment vets people, and the lack of mitigations put in place to get around the security concerns.

The Guardian later revealed that Mandelson’s associations with senior figures in China, Russia and Israel were among the concerns raised by the UKSC when it concluded he should be denied clearance.

The Foreign Office also refused to hand over a summary of Mandelson’s security vetting to the official tasked with compiling documents detailing the former Labour peer’s appointment as ambassador to the US, in response to a Commons motion forcing the release of documents linked to the process.

However, there was strong support for Robbins within Whitehall, with senior civil servants said to believe he was in effect sacked for doing what No 10 wanted by swiftly passing Mandelson through vetting, arguing the focus should be on the prime minister’s initial decision instead.

Robbins is understood to have been considering legal action against the government for damage to his reputation. Sources told the Guardian that Burnham’s team regarded him as an “outstanding operator”.

Sources said the most likely position for Robbins in a Burnham-led Downing Street operation would be that of national security adviser – a senior official in the Cabinet Office who serves as the principal adviser to the prime minister on national security matters.

The role has been held by Jonathan Powell, previously Tony Blair’s chief of staff in Downing Street, since November 2024, and while he received plaudits for his handling of international issues including Trump tariffs and the Iran conflict, he was criticised for the Chagos Islands deal.

Robbins, a former deputy national security adviser and also the UK’s former Brexit negotiator, would fit the bill in terms of a heavyweight replacement. Some Labour MPs have expressed concern that Burnham’s operation is currently “underpowered” on foreign and defence issues.

Asked about speculation over his appointment on a visit to Poland, Cooper told ITV: “You wouldn’t expect me to comment on individuals or individual appointments. I said at the time, Olly Robbins has a huge career in public service as a dedicated public servant.”

The removal of Robbins, who had been the permanent under-secretary at the Foreign Office since January 2025, triggered a briefing war, while the former official himself later told a committee of MPs that he was subject to “constant pressure” to get Mandelson in post as soon as possible when he started working at the Foreign Office.

Starmer has come under intense pressure to explain the process behind appointing Mandelson, a decision that many Labour MPs believe exemplified the prime minister’s poor political judgment. Some described Robbins’ testimony at the end of April as a key moment in determining whether they would turn against him.

Appearing before the foreign affairs select committee, Robbins joked that he had plenty of time on his hands following his dismissal. However, the offer of a role at the heart of a Burnham-led government would be a chance for one of the most high-flying members of his generation of civil servants to restore his reputation at Westminster.

Robbins had taken over from Sir Philip Barton as permanent under-secretary at the Foreign Office. He had been on the shortlist in 2024 to take over as cabinet secretary but failed to get the civil service’s top job.