Foreign Secretary admits national security clearance began only after Peter Mandelson was named UK envoy to the United States—triggering a political firestorm that ended in his sacking and a scramble to repair trust.

LONDON — The government has confirmed that Lord Peter Mandelson was not subjected to full national security vetting before No 10 announced him as Britain’s ambassador to Washington in December 2024—an admission that has detonated a week of political crisis, culminated in his removal, and raised fresh questions about how the state handles its most sensitive appointments.

In a letter to the Foreign Affairs Committee dated 16 September, Foreign Secretary Yvette Cooper and the Foreign Office’s top civil servant, Oliver Robbins, said the Cabinet Office’s Propriety and Ethics Team carried out due diligence before the announcement but that this was not a security check. They added that ‘the ambassadorial appointment process, including National Security Vetting,’ began only after the public unveiling on 20 December 2024, and that Mandelson ultimately obtained Developed Vetting before taking up the post on 10 February 2025 (FCDO letter to FAC, 16 Sept 2025).

The disclosure came days after Prime Minister Keir Starmer sacked Mandelson as ambassador to the United States following the publication of emails that revealed the depth of his relationship with the late convicted sex offender Jeffrey Epstein. In the Commons, ministers said the emails were ‘new information’ and showed the ‘depth and extent’ of the ties were materially different from what had been understood at the time of appointment (Reuters; The Guardian).

Among the most incendiary lines were Mandelson’s 2008 messages to Epstein—‘fight for early release’ and ‘I think the world of you’—sent as the financier faced sentencing in Florida. The correspondence, first detailed in a Bloomberg News investigation and amplified by UK outlets, cut through Westminster’s defences and made Mandelson’s position untenable (Bloomberg; The Guardian).

The affair has reopened an age-old fault line in British public life: the tension between political instinct and institutional process. The Foreign Affairs Committee chair, Labour’s Dame Emily Thornberry, accused the system of ‘a lack of rigour’, asking whether obvious red flags—notably Mandelson’s association with Epstein—were missed or waved through. She argued that the committee should have been allowed to question Mandelson before he was confirmed, a request the government declined at the time (The Guardian; Hansard).

Ministers insist the clearance system functioned as designed. Foreign Office minister Stephen Doughty told MPs that national security vetting is an independent process run by UK Security Vetting and that ministers are told only the final outcome, not the underlying material. He also signalled the government is open to ‘considering options’ for greater parliamentary scrutiny of future high‑stakes diplomatic nominations (The Guardian).

Yet politically, the damage was immediate. The prime minister had defended Mandelson only a day before the dismissal, saying he would not ‘rush to judgment’; by Thursday, he had withdrawn his envoy. The timing was disastrous: the scandal unfolded on the eve of President Donald Trump’s state visit, injecting an avoidable drama into a pivotal week for UK–US relations (Reuters; The Guardian).

Downing Street has named James Roscoe, the embassy’s deputy head of mission, as interim chargé d’affaires while a permanent ambassador is chosen—a steady pair of hands intended to assure Washington that the relationship is larger than any one figure. Roscoe, a career diplomat and former UK envoy at the UN, assumed the role immediately (Evening Standard; The Independent).

Inside Whitehall, some officials argue that the real failure was not the sequencing of checks but the political calculus. Proponents of the appointment say Mandelson’s contacts and instincts made him uniquely suited to manage a volatile Washington; critics reply that his history—from past interactions with sanctioned Russian businessman Oleg Deripaska to lucrative advisory work—made him an especially high‑risk pick for a role that demands unassailable judgment (Reuters).

Process, however, is where the cross‑party consensus now points. At minimum, MPs across the House want two changes: first, a guarantee that full security vetting is completed before any high‑profile national‑security appointment is announced; second, a formal pre‑appointment hearing for ambassadors to strategic allies such as the United States. Both steps, advocates say, would insulate prime ministers from avoidable missteps and reassure allies that London’s system is predictable and robust (Hansard; The Guardian).

Beyond Westminster’s blame game, diplomats in Washington worry less about personalities than about continuity. Mandelson’s short‑lived posting had early successes—he was praised inside government for his outreach to businesses and on trade—but the abrupt exit creates avoidable friction. It complicates preparations for the next phase of bilateral trade talks, intelligence cooperation forums and the choreography around the state visit. Allies value discretion and reliability; being forced to explain a scandal mid‑briefing is nobody’s idea of soft power (Reuters).

The government’s defence—that the clearance outcome was positive when Mandelson boarded his flight to Dulles—misses the point, says one senior official involved in major appointments. ‘Vetting is not just a pass/fail stamp; it’s a risk‑management exercise,’ the official argues. ‘The order in which you do things signals how seriously you take the risks. Announcing first and vetting later reads like politics first, process second.’

Inside the Cabinet Office, officials note that priority clearances—accelerated vetting—are a standard offer for urgent appointments and, they insist, do not dilute the checks. Cooper and Robbins’ letter confirms Mandelson’s Developed Vetting was granted ‘in advance’ of him taking up post in February, and that the FCDO requested a faster decision to ensure a timely arrival in Washington (FCDO letter to FAC).

What the letter could not solve is the optics of chronology. By admitting that full vetting began only after the appointment was public, the government conceded a sequencing that looked cavalier in hindsight. The emails ensured that hindsight arrived with a vengeance. In politics, process is a proxy for judgment; and on this appointment, many MPs now say, judgment failed.

For the victims of Epstein’s crimes, the episode has been yet another painful reminder of how power circles shield themselves. Opposition leaders have urged the prime minister to apologise to survivors and to publish documents related to the appointment. Starmer has said only that he was ‘let down’ and that, had he known then what he knows now, he would not have appointed Mandelson (The Guardian).

There remains the question of what, exactly, the government knew and when. Ministers say the most damaging emails were not seen during the vetting; some MPs do not accept that. A formal document release or a Privileges Committee inquiry could, in time, adjudicate the dispute. In the meantime, Britain’s most important diplomatic posting is run by a caretaker at a delicate moment in global affairs.

If there is a workable lesson, it is procedural humility: finish the checks before the fanfare; subject political appointees to the same daylight routinely applied to regulators and central‑bankers; and treat alliances as institutions, not photo opportunities. Washington will not remember the precise wording of a Commons statement. It will remember whether London kept its house in order.

Sources: Letter from Yvette Cooper and Oliver Robbins to the Foreign Affairs Committee, 16 Sept 2025; The Guardian reporting on vetting chronology and parliamentary debate, 16–17 Sept 2025; Reuters wire on dismissal and the government’s rationale, 11 Sept 2025; Bloomberg News reporting on the Mandelson–Epstein emails, 11 Sept 2025; The Independent/Evening Standard on interim appointment of James Roscoe, 11–12 Sept 2025; Hansard record of parliamentary exchanges, 16 Sept 2025.