Britain’s ambassador to Nato has triggered a diplomatic row after moving an Italian girlfriend nearly half his age into his official Brussels residence, The Times has learnt.
Another top diplomat raised concerns after Angus Lapsley, 55, started a relationship with an intern he met at Nato headquarters in Brussels while he was in a senior planning role.
The UK’s incoming ambassador to the EU, Dame Caroline Wilson, thought it was “inappropriate” Lapsley should now live with the woman — previously his assistant — in the residence, according to an informed source. The Times has chosen not to name the woman.
The Foreign Office refused on Wednesday night to say where Lapsley currently lived.
The father of two’s relationship with his assistant, now in her late twenties, was deemed so significant inside Nato that it crossed the desk of Admiral Sir Keith Blount, the deputy supreme allied commander Europe and the most senior British officer in Nato.
However, after the policy on Nato relationships was reviewed to see whether he had broken any guidelines, Lapsley was allowed to continue in the post and was promoted by the British government to ambassador, sources said.
Nato does not have any rules against relationships concerning senior officials with subordinates, it is understood. Relationships with subordinates in the UK military can be a sacking offence.

Dame Caroline Wilson
GOV.UK
For example, Admiral Sir Ben Key, the former first sea lord, was thrown out of the Royal Navy last year and stripped of his rank after he had an inappropriate relationship with a subordinate.
A Nato official said: “Nato requires all managers to declare any real or perceived conflict of interest. This policy is longstanding and has not been changed in recent years.”
Lapsley was the assistant secretary-general for defence policy and planning at Nato until March last year, before his promotion to UK ambassador to Nato in April.
Previous holders of the role have been given a home in the shared diplomatic townhouse on Rue Ducale, a former hotel facing Brussels Park.

Admiral Sir Ben Key
MAX MUMBY/INDIGO/GETTY IMAGES
Although Lapsley is entitled to a residence, it is understood that any decision over the use of the former Hôtel de Croÿ is ultimately up to Wilson.
Wilson, a former lawyer and recently the UK’s ambassador to China, is expected to take over the top job at the UK mission to the European Union later this year. She will live in the residence on Rue Ducale, which already hosts Anne Sherriff, the British ambassador to Belgium.
On Tuesday night Lapsley pulled out of a briefing at Nato headquarters in Brussels planned the following day, as the Foreign Office prepared for details of Lapsley’s relationship to be made public.
A defence source said that the relationship was an open secret in Brussels.
They said: “They have made no attempt to hide their relationship. Angus used the residence as if it was his, and [the woman] was there [for] Christmas and summer receptions.”
The Foreign Office refused to comment on whether Lapsley was living in the residence with the woman and whether British taxpayers were paying.
Lapsley is no stranger to controversy. In June 2021, while on secondment to the Ministry of Defence from the Foreign Office, he left 50 pages of top-secret documents behind a bus stop in Kent.
The Times later revealed the secret locations of British special forces soldiers in Kabul were among the classified documents and their loss sparked a transatlantic row.
The Americans were furious, according to a Whitehall source in 2022, because of concerns the breach could endanger the lives of elite US soldiers.
At the time of the incident, Lapsley’s security clearance was suspended but after an investigation it was reinstated.

Lapsley at the Nato Summit in July 2023 in Vilnius, Lithuania
PAULIUS PELECKIS/GETTY IMAGES
Lapsley was the director-general for strategy and international at the MoD at the time and had been lined up to become the UK’s ambassador to Nato.
He returned to the Foreign Office but for months it was unclear what his role was. It then emerged in 2022 he had been given a planning role at Nato.
• Official who left secret files at bus stop set for British Nato role
The Times can now reveal that the top-secret documents were not the only papers he left behind.
A source inside the MoD said Lapsley also left behind at least one personal diary, which resulted in Ben Wallace, the defence secretary at the time, later calling for his security clearance to be reconsidered.
The source said Lapsley used the diary to express his frustration at the department and wrote about his relationships with individuals.
Wallace wrote to the Cabinet Office because he felt his vetting should be examined after the diary was discovered.
Speaking candidly about Lapsley for the first time, Wallace said of the diary: “It is not acceptable that the Foreign Office and others persisted to ignore concerns raised by me and others about this individual. Officials, by ignoring ministerial direction, have now risked the UK’s reputation in Nato and undermined security.”
One defence source said the department was not aware of the diary or any security concerns related to it.
Lapsley declined to comment.
A Foreign Office spokeswoman said: “It is longstanding policy not to comment on personnel matters.”