Smoking should be completely banned in the UK, according to a top medical journal.
Passive smoking kills 1,000 people each year, the Lancet says
The Lancet said tens of thousands of lives would be saved by making tobacco an illegal substance and possession of cigarettes a crime.
It said 80% of Britons were non-smokers, who had "the right to freedom from exposure to proven carcinogens".
An estimated 1,000 people a year in Britain died from inhaling second-hand tobacco smoke, its editorial claimed.
Smokers group Forest greeted The Lancet's call with "amusement and disbelief".
It said: "Like it or not, people choose to smoke,
just as they choose to drink alcohol, eat certain types of food, or take part in extreme sports."
According to the Lancet passive smoking not only kills, but makes it more difficult for smokers to quit.
It highlighted a study by the Royal College of Physicians, which said that if all the workplaces in the UK became smoke-free 300,000 more people would stop smoking.
That alone would save 150,000 lives, it said.
Dr Astrid James, deputy editor of the Lancet, told BBC Radio 4's Today programme that smoking created a "public health burden", killing 120,000 in the UK and 4.2m worldwide every year.
She said bringing an end to smoking would prevent a third of deaths due to cancer in the UK, one in seven deaths from heart disease and most deaths and illness due to chronic lung disease.
"Why do we allow a product that kills?" she said.
But chief executive of the Tobacco Manufacturers' Association Tim Lord said millions choose to smoke despite knowing the risks.
He said a suggestion by Dr James that many smokers and non-smokers didn't realise the extent of the burden on society, was "patronising".
"To say that people don't understand the health risks associated with smoking when on every single pack there are enormous health warnings, I just find unbelievable," he told Today on Friday.
The medical journal also argued that the cost of cigarettes and tobacco was less important than availability and acceptability.
"Cigarette smoking is a dangerous addiction," it said.
"We should be doing a great deal more to prevent this disease and to help its victims. We call on Tony Blair's
government to ban tobacco."
Dr James said the government had already shown it was willing to pass similar legislation, such as banning the use of hand held mobile phones while driving.
She said: "That was in the face of 20 deaths over five years."
"Why is the government not taking a stronger stance here?"
The Lancet also questioned the government's claim that the British public was still to be convinced of the need for a public smoking ban, as introduced in parts of the
US, Canada, Thailand, and southern Australia.
It said ordinary people were better equipped to consider the arguments than the government, "perhaps because the UK public does not have to consider directly the £9.3bn per year raised in tax revenue on tobacco".
In comparison, the £1.5bn cost to the NHS of smoking-related diseases was "paltry", the Lancet argued.
It made its case a month after leaders of the 18 Royal Colleges of medicine wrote a letter to The Times attacking the government's failure to ban smoking in public.
Forest director Simon Clark said the Lancet was "the true voice of the rabid anti-smoking zealot".
He said smokers should not be treated as criminals, adding: "The health fascists are on the march.
"What next? Will they urge the government to ban fatty foods and dairy products?"
Health Secretary John Reid said the government had made a big investment in trying to help people give up smoking.
But he said: "Despite the fact that this is a serious problem, it is a little bit extreme for us in Britain to start locking people up because they have an ounce of tobacco somewhere."
Deborah Arnott, director of the anti-smoking charity ASH, said: "A legal ban on smoking is neither possible nor desirable. We want to help and encourage people not to smoke, not to force them."