We regret, however, the necessity to censor part of a film directed at a mature adult audience

British Board of Film Classification

The film follows two women who go on a rampage of sex and violence after one of them is raped.

It has now been given an 18 certificate by the British Board of Film Classification (BBFC) who felt the film in its original form was not suitable even for R18 porn films.

In one scene in the film a man is stamped to death by a woman wearing high heels after he is picked up for sex.

'Sexual imagery'

The BBFC said of the removed shot: "Its extreme sexual imagery is unmatched elsewhere in the rape scene.

The RSPCA expressed concern about scenes in Amores Perros

"Without it, the sequence remains a compelling portrayal of the ugliness and horror of rape. With it, the scene takes on a more explicitly pornographic dimension and is a matter of serious concern."

But the censors said they had made their decision with reservations.

"We regret, however, the necessity to censor part of a film directed at a mature adult audience who may reasonably expect to make up their own minds about it," the organisation said.

The film contains several graphic sexual images but the BBFC pointed out that none of them are associated with rape or violence.

'Serious concern'

"It is also relevant that the two female protagonists remain in control of events - the most serious concern identified by effects research, which is male sexual aggression, is not an issue in the rest of the film," the BBFC said.

Last year the BBFC relaxed rules on 18-rated films, embracing a more liberal approach where audiences are allowed to make up their own minds.

Another controversial film, the Oscar-nominated Amores Perros, has been passed uncut after complaints about dog fighting scenes.

The BBFC has given it an 18 rating after being satisfied that no animals were harmed in the making of the Mexican movie.

The Royal Society for the Prevention of Cruelty to Animals was among organisations concerned about the scenes.

The film has been nominated for a best foreign language film Oscar.