An Oxford professor has warned cigarettes are so lethal that the Government should act now to stub out the habit in public places.

Dr David Matthews, Oxford University's Professor of Diabetes, believes ministers will miss a vital opportunity to improve the nation's health if they do not introduce a smoking ban.

He welcomed Oxford City Council's consultation asking residents for their opinions, and criticised claims that pubs and clubs would suffer financially if prohibition came into force.

Prof Matthews said: "The economic arguments put forward say banning smoking will have a big impact on the hospitality industry.

"That view doesn't take into account that smokers are literally dying. Dead people don't drink, and that's not going to have a positive impact on the hospitality industry.

"Smoking is much more dangerous than driving fast in a car. It takes so many people's lives early.

"Economists value someone's life for one year at £30,000 and what that means is that if I spend £30,000 on you and you live a year longer that's seen as a reasonable investment. If I spend £100,000 that's regarded as a bad investment. Anything you do to prolong people's lives for cheaper than £30,000 is good value, and banning smoking in public places would be a very good investment in the nation's health."

Prof Matthews heads the Churchill Hospital's Oxford Diabetes Centre, and has witnessed the destruction tobacco causes. He said: "The problem with smoking and diabetes is that they give you early heart disease. It's a sort of double whammy against your body and people die early.

"Smoking is exceedingly dangerous, and we're trying to help people stop smoking because it's one of the things we can do to preserve people's lives."

Prof Matthews is part of the Oxford Vision 20 20 research programme, looking at how to change attitudes towards smoking, diet and exercise -- the three main risk factors for chronic illnesses like heart disease, diabetes and cancer.

The study has shown people's views towards lifestyle will only change if different strategies are combined to educate them.

He said: "Cigarette smoking is a good example of changing views. If you use warnings on packets, fiscal measures of taxation, ban advertising, introduce education programmes and ways of giving up on the NHS, and a sustained media campaign, it works."

Michael Rolley, of Oxford and District Licensed Victuallers, said even if people lived healthier, longer lives, many pensioners had financial worries and could not afford to drink in pubs. He said: "Smoking and drinking have always gone together and I suppose we'll have to wait and see if a ban makes a difference to trade.

"In Ireland and New York it's made a difference even though the non-smoking people are doing their utmost to justify it and say that financial losses would have happened even without the smoking ban."