More than 680,000 people set a quit date last year
A controversial pill is boosting the success of smokers in England in kicking the habit, NHS figures suggest.
One in seven people trying to quit are using Champix, according to the first figures published since the stop smoking drug was licensed in 2006.
And NHS Information Centre data showed 63% of people were successful last year at the four-week mark compared to half using nicotine replacement therapy.
Champix has come under scrutiny over reports it causes suicidal feelings.
The Medicines and Healthcare Products Regulatory Agency says it is "closely" monitoring the drug after almost 3,000 reports of adverse reactions.
So far there have been more than 200 reports of suicidal thoughts in patients taking Champix.
And more than 350 reports of depression, although these have mainly involved patients who had an underlying psychiatric illness.
The drug is unusual as it both stimulates and blocks specific nicotinic receptors in the brain.
By stimulating the receptor it is thought to mimic the effects of nicotine to reduce cravings.
At the same time, it partially blocks the receptor preventing nicotine from binding to it, resulting in a weaker response in people who give in to temptation and have a cigarette.
Trials suggested around 44% of smokers give up after taking the drug twice a day for 12 weeks, compared with 18% of those given a placebo and 30% of those taking another major anti-smoking drug, bupropion.
The latest figures show that in 2007-8 - the first year since the smoking ban was introduced - there was a 13% increase to 680,000 in the number of people setting a quit date.
There was also a 10% rise to 350,800 in the number of people who had stuck to their attempts to quit after four weeks.
NHS Stop Smoking Services spent almost £61 million in the past year on helping people to quit - nearly £10 million higher than the year before.
Health minister Ann Keen said she was delighted with the increase in people successfully quitting smoking.
"I'd like to take this opportunity to say congratulations to all those who have made such positive efforts to kick the habit - very well done.
"This shows that the investments that we are making in helping smokers to quit are having a positive impact."