The chief of the Secret Intelligence Service, MI6, has issued a public apology for the agency’s past treatment of LGBT+ people.

Richard Moore said that a security bar on LGBT+ individuals serving in the intelligence agencies, which remained in place until 1991, was “wrong, unjust and discriminatory”.

In a video statement posted on Twitter, Mr Moore, known in Whitehall as C, said it had resulted in the lives of committed professionals being blighted while others were denied a chance to serve.

Although same-sex relationships were decriminalised in 1967, the ban on LGBT+ people serving in the agencies and the diplomatic service stayed following a series of Cold War spy scandals.

Two of the Cambridge spies, Guy Burgess and Anthony Blunt, were gay while a third, Donald Maclean, may have been bisexual.

Mr Moore said it was down to a “misguided” belief that LGBT+ people were more susceptible to blackmail.

Committed, talented, public-spirited people had their careers and lives blighted

“It meant that until 1991, being openly LGBT+ in MI6 would cause you to lose your job or prevent you from being allowed to join in the first place,” he said.

“Committed, talented, public-spirited people had their careers and lives blighted because it was argued that being LGBT+ was incompatible with being an intelligence professional.

“Because of this policy, other loyal and patriotic people had their dreams of serving their country in MI6 shattered.

“This was wrong, unjust and discriminatory.

“Today, I apologise on behalf of MI6 for the way our LGBT+ colleagues and fellow citizens were treated and express my regret to those whose lives were affected.

“Being LGBT+ did not make these people a national security threat.

“Of course not.

“But the ban did mean that we, in the intelligence and diplomatic services, deprived ourselves of some of the best talent Britain could offer.”

Mr Moore said that even after the ban was lifted, its effects lingered on in the agency.

“Some staff who chose to come out were treated badly for not having previously disclosed their sexuality during their security vetting,” he said.

“Others who joined in the period post-1991 were made to feel unwelcome.

“That treatment fuelled a reluctance to be their true selves in the workplace.

“This was also unacceptable.”

Mr Moore paid tribute to the “extraordinary resilience and loyalty” shown to MI6 by LGBT+ staff past and present.

He said the service still had more to do to be a fully inclusive employer and that his goal was to make it “a workplace where you can always bring your true self to work”.

Foreign Secretary Dominic Raab tweeted: “I join @ChiefMI6 in paying tribute to the extraordinary courage and dedication of LGBT+ colleagues, past and present, in the intelligence community. The UK is safer because of their dedicated service.”