Local councils in London are considering asking Parliament for powers to impose a smoking ban.
The Association of London Government (ALG), which represents the councils, is drawing up a list of measures to include in a Bill this November.
The issue of smoking bans is among proposals already put forward by the councils, with Enfield in north London leading the call.
But a spokesman for the ALG said reports that the smoking issue would definitely be included in the Bill were "jumping the gun".
"Nothing's ruled in and nothing's ruled out," he said.
A spokesman for Enfield council said the authority was not looking for a blanket ban on smoking.
It planned to take a three-stage approach, first taking a tough line on smoking in offices in the borough, then making sure all pubs and restaurants had separate smoking areas, and finally persuading businesses such as nightclubs to take a more responsible attitude to passive smoking.
But the spokesman added that the council was "not looking to drive business away from Enfield."
He said: "We want to work with business, but we're also mindful of trying to protect the public health of our residents as well as workers in the public entertainment and hospitality industry."
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