Sir Olly Robbins, the government's former lead official on Brexit, is taking legal action against the government following his dismissal as head of the Foreign Office, the FDA union announced. The union represents senior civil servants.

The FDA says the decision to sack Sir Olly was based on a "grievous misunderstanding" of how government vetting procedures work. Its legal argument goes further: it will challenge whether Prime Minister Sir Keir Starmer had the legal power to dismiss him at all. If successful, the case would affect not just Sir Olly but the broader rules around how prime ministers can remove permanent secretaries — the most senior civil servants in each government department.

Sir Olly was appointed to the Foreign Office role in early 2025. During the previous decade he had been the government's chief negotiator with the EU over Brexit, a role that made him a well-known figure in Westminster. His dismissal came after a row over how the security clearance of Lord Mandelson had been handled. Questions were raised in Parliament about whether the vetting process had followed proper procedure.

The FDA's case turns on what Sir Olly was and was not allowed to tell ministers. The union argues he was bound by confidentiality rules that prevented him from disclosing details of the vetting process used to assess Lord Mandelson. When giving evidence to MPs, Sir Olly said he had received only an oral briefing — spoken information — about the case, rather than written documents from UK Security Vetting, the agency responsible for checking security clearances. BBC He was told Lord Mandelson was a "borderline case" but that the Foreign Office might grant clearance if proper safeguards were in place.

Sir Olly's defence rests on confidentiality. He told MPs that vetting processes must "remain absolutely confidential." Combined with the FDA's argument about his obligations to keep such information private, this forms the heart of his case: he acted within the rules of a system designed to protect vetting decisions from political pressure, and was dismissed for following those rules.

The FDA has been direct about its view of the dismissal. Dave Penman, the union's general secretary, has led the response. The union said there was "no fair procedure involved in his dismissal" and "no process at all." FDA The union first condemned the decision in April and has now moved to formal legal action.

Sir Olly himself has sounded reluctant about the case. He said he is pursuing it "reluctantly" and suggested the whole dispute could have been avoided. An apology and compensation from the Prime Minister, he indicated, would have made the legal action unnecessary. That suggests vindication and acknowledgment of wrongdoing may matter more to him than getting his old job back.

At first glance, this case involves two separate questions: whether Lord Mandelson's security clearance was handled correctly, and whether the official managing that process was sacked lawfully. The FDA's legal strategy appears designed to keep these distinct. Whatever one thinks about the vetting decision itself, the union argues, the dismissal followed no recognisable procedure.

Where this case may matter beyond Sir Olly is in the position of permanent secretaries more widely. Permanent secretaries work within long-standing rules about how ministers can act and what must stay confidential in security matters. A court decision that the Prime Minister overstepped his power in removing the head of the diplomatic service would carry weight throughout the civil service. Such a judgment could reshape how senior officials and ministers work together — a prospect Whitehall will be watching closely, whatever the court decides.

No date has been set for the legal hearing, and the government has not yet offered a detailed public response to the FDA's claims about flawed procedure. The case reflects wider tensions between senior civil servants and the current government over where ministerial power ends. Other permanent secretaries will be watching to understand how far they can rely on confidentiality rules in security matters — and whether those same rules might put them at professional risk.