A prominent research firm has apologised over a tobacco survey which some see as an attempt to recruit new smokers.

For British American Tobacco, Colmar Brunton pitched the survey to 10,000 people, saying that depending on their answers, they may be asked to join a study in which they would be given cigarettes to smoke.

They would also be given $40 and 20 Fly Buys points to cover the cost of any expenses.

The Ministry of Health has contacted Colmar Brunton after receiving complaints. Public health advocacy group Action on Smoking and Health (Ash) wants the ministry to prosecute.

Ash said yesterday: "The Smokefree Environments Act prohibits tobacco products being distributed or supplied free of charge. The act makes it clear that tobacco products cannot be offered with gifts, cash rebates or the right to participate in any contest or game."

Ash director Ben Youdan said tobacco companies had said they didn't want to recruit non-smokers, but this was contradicted by the offer of free cigarettes being made to smokers and non-smokers.

He accused the tobacco industry of showing a blatant disregard for smokefree laws.

Colmar Brunton's executive chairman, Dick Brunton, said about 20 people had complained to the company. He had written to them to apologise over the "clumsy" wording of the invitation to take part in the survey.

"I think about 20 people out of 10,000 have interpreted it as being an incentive or promotion or encouraging people to smoke.

"Which is a shame, because that was certainly never our intention or our client's intention, but I do concede that the way it was done and presented, I could see how some people could jump to that conclusion."

The online survey screened for smokers - smokers of certain brands - to be selected into the subsequent study in which they are asked to smoke the test cigarettes and give their views about them.

One occasional Colmar Brunton research participant, a non-smoker who asked not to be named, complained to the Herald about the survey. "Surely this is borderline promotion of smoking, or if nothing else, a heady temptation for those trying to quit," she said.

Mr Brunton asserted the project complied with the law.

"The cigarettes were not a bribe. The reward was cash and the Fly Buys points. They were given enough cigarettes to test them , to smoke them - the cigarettes were not the reward.

"We aren't allowed to reward people with cigarettes. We did want people to smoke some cigarettes. That's perfectly within the law. Our client is absolutely paranoid about following the law."

British American's head of corporate and regulatory affairs, Susan Jones, said Colmar Brunton had accepted responsibility for breaching protocols agreed with the tobacco company. These included that only age-verified adult smokers were sought.

The ministry said it was "looking into possible legal issues" raised by the research. When asked if it would prosecute, the ministry said the suggestion was premature.

"However, the ministry views with concern any activities that seek to undermine its efforts, and the gains made so far, to further reduce smoking prevalence in New Zealand."