An anti-smoking group in Liverpool is calling for all movies with smoking scenes to be given an 18 certificate.
SmokeFree Liverpool told
BBC's Radio 5 Live it wanted to see the change but the film classification board said the idea was "heavy-handed".
The push - backed by the city council - comes amid research showing young people pick up the bad habit from watching films containing smoking.
One city official said Liverpool may even act alone to restrict film access.
Andy Hull, the city's head of public protection and chair of SmokeFree Liverpool, said an adult rating on movies that depict smoking will reduce the number of young people lighting up.
"The international evidence...is that one in two children between 11 and 18 who witness smoking in movies actually experiment with - and therefore start - smoking themselves," Mr Hull said of recent research. Liverpool already carries the unenviable title of lung cancer capital of England, with some of the highest smoking rates in the UK.