Managers of an historic East Finchley cinema have said they are “disappointed” after discovering a porn video was filmed inside the iconic building.

The seven-minute film, showing a group of women watching a man and woman carry out a sexual act at the Phoenix Cinema in High Road, has gone viral on the internet.

The erotic footage has been posted on as part of a series of CFNM films, which means Clothed Female Naked Male.

The discovery has caused a stir on social networking sites, but the managerial team at the Phoenix have denied it happened on their watch.

A spokeswoman told the Times Series: “It was obviously a long time ago. No one who is here was here then. It was done without our knowledge and we do not normally do anything like that.”

She said the cinema is “scrupulous” about monitoring groups who hire the venue, but added that “unfortunately this one slipped through the net”.

The cinema, which celebrated its centenary in 2012, can be hired out for children’s parties as well as for corporate functions, charity events and private parties.

It is recognised as one of the UK’s longest running, purpose-built cinemas and has a number of celebrity patrons including comedian Victoria Wood, actor Michael Palin and film critic Mark Kermode.