A new study of 900 smokers indicates that most underestimate how long it will take them to quit.

The study found more than half of all smokers expect to stop within two years when only six per cent succeed.

The research, published in the British Medical Journal, also found four out of five smokers would not take up the habit if they had their time again.

Forum Response: Cancer Research UK

Professor Martin Jarvis, principal scientist at Cancer Research UK, told ePolitix.com: "There is a yawning gulf between smokers' wildly overoptimistic expectations of future quitting and the dismal reality.

"This delusion gap probably reflects wishful thinking more than hard-headed calculation, but it does tend to confirm that most smokers have a desperate desire to be rid of tobacco.

"The tobacco companies talk about free adult choice, but they are selling an addictive drug and people consume it because they are hooked, and not because they choose to."

Forum Response: British American Tobacco

A spokesperson for British American Tobacco told ePolitix.com: "It has been known for centuries that smoking may be difficult to quit and we accept that the common understanding today is that smoking is addictive.

"Certainly smoking is pleasurable and smokers can find it hard to quit even though they know that smoking is a real risk for serious diseases. People realise that someone who starts smoking may find it difficult to quit.

"However, we believe it is also important that smokers who decide to quit realise that they can, provided they have the motivation to quit and belief that they can.

"Millions of smokers have quit without any medical help, and millions have modified how often, where and when they smoke in the light of differing social norms. In some countries, such as the UK, there are now more ex-smokers than smokers."