The London Gay Men’s Chorus will be singing at London mayor Boris Johnson’s Christmas carol service at Southwark Cathedral next week.

It will be the first time the chorus, which is the largest gay men’s singing group in Europe, has sung at this event.

Johnson will not be present at Tuesday’s event as he is attending a climate change conference in Copenhagen.

Instead, deputy mayor Richard Barnes will take his place.

Johnson said: “The carol service at Southwark Cathedral will celebrate our Christian heritage and our core values of tolerance, creativity, respect for the rich diversity which makes London the best big city on earth.”

Chair of the chorus Anthony Fordham added: “As singing ambassadors for the gay community, we are especially pleased to be taking part in this carol service as part of our ongoing relationship with the GLA [Greater London Authority].

“The evening promises to include a mixture of both the traditional and not so traditional seasonal music and will be accessible to a very diverse audience.”

The GLA Christmas Carol Service follows last year’s event at the historic place of worship, which is close to City Hall and the Thames.

The theme of the event will be ‘Service to Londoners’, in recognition of the work of the police, the fire service, ambulance and nursing staff, as well as the armed forces.

Attendance is free but those wishing to join the service are asked to email carolservice09@london.gov.uk