More than three-quarters of people in London would prefer enclosed public places in the city to be completely smoke-free, a poll has revealed.
A handful of pubs and restaurants are already smoke-free
Tens of thousands of Londoners aired their views in the Big Smoke Debate.
The poll was launched by the London Health Commission (LHC) to find out how much support there would be for a complete public smoking ban.
But a smokers' lobby group claimed the survey is "flawed" with less than 0.5% of Londoners voting.
Chief medical officer Sir Liam Donaldson and UK doctors have already called for an end to public smoking, but the Department of Health has so far indicated there are no plans for such a ban.
Of the 34,446 Londoners polled, 37% of people would prefer public places to be smoke-free but only indoors, with 41% preferring a ban on cigarettes both inside and out.
More than 64% said they wanted restaurants to be free of smoke, with 43% saying the same of pubs and bars.
At the moment only a handful of pubs and restaurants are smoke-free, despite a voluntary agreement signed by the hospitality industry in 1998 to increase smoke-free areas.
LHC chairman Len Duvall said: "The results of the Big Smoke Debate have shown us that there is a desire for change, with overwhelming support for smoke-free public places in the capital.
"There is a perception, particularly within the hospitality industry, that going smoke-free will result in a reduction in business, but this is not the case.
"Smoke-free policies make sense for business as we have seen in smoke-free cities such as San Francisco where there has been either a neutral or positive effect on profits."
The Freedom Organisation for the Right to Enjoy Smoking Tobacco (Forest) said three million households were invited to take part in the survey with only 34,500 votes cast. Nearly eight million people live in London.
Director Simon Clark said: "The Big Smoke Debate was flawed from the start and the results are boringly predictable.
"Respondents were self-selected so the poll reflects those with strong opinions, not the moderate majority."
The LHC is presenting the views expressed in the poll to businesses and London mayor Ken Livingstone in a bid to influence policy on smoking.
Mr Livingstone said: "A complete ban on smoking in all public places would require new government legislation and support for it varies, with backing for smoke-free restaurants and offices much higher than in relation to pubs and bars.
"But there is clearly a strong groundswell for a change to the current balance."