Scenes of smoking in American movies - as well as the traditional taboos of sex, violence and swearing - could lead to their minimum-age ratings being raised, it was today announced.

The Motion Picture Association (MPA), which which sets movie ratings in the US, has decided that "glamourised smoking" will now be a factor in how old viewers need to be to see a film.

The decision, announced by the organisation's chairman Dan Glickman, was designed to placate a growing lobby of activists in the US who claim that impressionable youngsters watching film stars smoking are more likely to take the habit up themselves.

However, some anti-smoking groups claim that the chairman's statement making smoking "a factor" in the decision-making process does not go far enough. They have instead demanded a mandatory minimum 'R' rating for all films with smoking, meaning only those aged 17 or over, unless accompanied by a guardian, could attend.

In a statement, Mr Glickman said: “The rating board will now consider smoking as a factor, among many other factors, including violence, sexual situations and language, in the rating of films.

“Clearly, smoking is increasingly an unacceptable behaviour in our society. There is broad awareness of smoking as a unique public health concern due to nicotine’s highly addictive nature, and no parent wants their child to take up the habit.

"The appropriate response of the rating system is to give more information to parents on this issue.”

Mr Glickman, however, rejected activists' demands for a mandatory R rating, claiming that it would not “further the specific goal of providing information to parents on this issue”.

Responding to the announcement, Kori Titus, a spokeswoman for the anti-smoking group Breathe California, said: “I’m glad it’s finally an issue they’re taking up, but what they’re proposing does not go far enough and is not going to make a difference."

In the US, film rankings are different to those in Britain. A film is ranked G if it is for general audiences, PG suggests parental guidance, PG-13 suggests parental guidance for children under 13, R is for movies restricted to viewers 17 or older unless accompanied by guardian, and NC-17 means no one under 17 will be admitted.

Today's American decision follows the British example, where the British Board of Film Classification (BBFC) says it already takes into account "works which promote or glamorise smoking" when classifying films.

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