Movies and cigarettes used to be as inseparable as Bogart and Bacall, with Hollywood glamorising the habit on and off-screen. But now films could earn a tougher rating if their characters light up.

Bowing to pressure from antitobacco activists, the Motion Picture Association of America (MPAA), which issues movie ratings, will take into account “depictions that glamorise smoking or movies that feature pervasive smoking outside of a historic or other mitigating context”.

Although activists have campaigned for a mandatory “R” rating for films featuring any smoking – meaning that children under 17 could not see them without a parent or guardian – the MPAA is pursuing a more subtle approach.

Dan Glickman, of the association, said: “This is an extension of our current practice of factoring underage smoking into the rating. Now, all smoking will be a consideration.”

British Board of Film Classification (BBFC) guidelines state that any glamorisation of smoking “may be a concern”.

A BBFC spokeswoman said yesterday: “Our examiners do log smoking in films . . . But we’ve never seen a film portraying smoking in such a way that we have had concerns.”

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