The animal charity said a number of people who have seen the film, which was written and directed by Guy Ritchie, have contacted them with concerns about certain scenes involving dogs.

The film is due to be released on Friday, but the RSPCA has asked for a special screening on Tuesday to assess its contents.

The film's makers could face prosecution if the charity uncovers evidence of real dog fighting.

'Offensive'

Its certificate is also dependent on the makers being able to guarantee that no animals were hurt during production.

"Obviously we are concerned as dog fighting is a particularly offensive crime involving people placing bets, in which the animals can suffer horrific injury," said a spokeswoman for the RSPCA.

"We have a specialist operations unit that tries to track down dog fights and they will be very interested in seeing the film.

"We are concerned with potential suffering to animals during filming, and also the potential for copycat incidents.