The head of the UK’s largest police force has apologised for past failings towards the LGBT+ community in what a renowned gay rights campaigner has hailed as a historic first.

Peter Tatchell thanked Metropolitan Police Commission Sir Mark Rowley “for being the first UK police chief to say sorry for decades-long victimisation” of this community.

The Peter Tatchell Foundation has been leading an #ApologiseNow! campaign calling on all UK police chiefs to apologise for past homophobic persecution.

The campaign was supported by the late television star Paul O’Grady before his death in March and a launch event at the House of Lords on Wednesday was attended by his partner, Andre Portasio.

Sir Mark, in a letter to Mr Tatchell, acknowledged that while police had to enforce the law at the time when homosexuality was criminalised, the way it was sometimes enforced had “failed the community and persist(s) in the collective memory of LGBT+ Londoners of all ages”.

The Met boss apologised in March in the wake of the damning report by Baroness Casey which found there is racism, misogyny and homophobia in the force.

I am clear that there is much for us to do. I am sorry to all of the communities we have let down for the failings of the past and look forward to building a new Met for London, one all Londoners can be proud of and in which they can have confidence

But Mr Tatchell said the apology he received by letter on Wednesday was a “ground-breaking step forward” that “draws a line under past Met persecution”.

It is hoped Sir Mark’s words will be repeated by other police chiefs in the UK, the campaigner said.

Part of the letter read: “The Met has had systems and processes in place which have led to bias and discrimination in the way we have policed London’s communities, and in the way we have treated our officers and staff, over many decades.

“Recent cases of appalling behaviour by some officers have revealed that there are still racists, misogynists, homophobes and transphobes in the organisation, and we have already doubled down on rooting out those who corrupt and abuse their position.”

It added: “I am clear that there is much for us to do. I am sorry to all of the communities we have let down for the failings of the past and look forward to building a new Met for London, one all Londoners can be proud of and in which they can have confidence.”

Mr Tatchell said: “We are not asking the police to apologise for enforcing the law, but to apologise for the often illegal and abusive way they enforced it.

“The police did not make the law but they chose to enforce it in ways that today would be deemed illegal and unacceptable.”

He added: “We thank Sir Mark Rowley for being the first UK police chief to say sorry. His apology is a ground-breaking step forward that will, we hope, spur other police forces to follow suit.

“It draws a line under past Met persecution. This will help strengthen LGBT+ trust and confidence in the police; encouraging more LGBTs to report hate crime, domestic violence and sexual assault.”