The Health Ministry said it was working on the idea of forcing tobacco retailers to be listed on a state register of tobacco outlets.
Having some form of register or licensing system is a policy promoted by both Action on Smoking and Health (Ash) and British American Tobacco.
Ash said a register would simplify and enhance the enforcement of tobacco control laws.
It is estimated New Zealand has up to 10,000 tobacco retailers.
Associate professor of public health Dr Nick Wilson, of Otago University at Wellington, said a register or licensing system would be a "small-fry" policy, but would provide a potential new penalty in the de-licensing of shops which illegally sold cigarettes to people aged less than 18.
Such a system could also lay the groundwork for the "big-picture" policy of reducing the number of tobacco outlets by holding an annual auction of a progressively shrinking number of licences.
However, the ministry said this week in its reply to the Herald's questions under the Official Information Act in February that although the idea of restricting the number of tobacco retailers was floated by an official in a discussion paper on tobacco policy last year, no further policy development work had been done on it.
Nor had the suggestions on making tobacco a prescription-only substance and imposing quotas on tobacco sales been progressed.
A deputy director-general of health, Cathy O'Malley, said "ongoing" work had been done since last May on the extension of smoke-free environment restrictions - particularly the prevention of smoking in cars containing children - and on the retail register idea, but she withheld it.
The material she did release, dated up to the end of last May, included an official's notes from a meeting with Associate Health Minister Tariana Turia. These state, in respect of any efforts to stop smoking in cars containing children: "We noted the Government's stated preference is for non-legislative options."
Dr Wilson said second-hand smoke in cars was a serious health hazard.
A number of jurisdictions in Australia and the United States had introduced laws against smoking in cars containing children and New Zealand, which had fallen behind on the issue, should do the same.
He said not legally banning the practice - and instead just discouraging it through social marketing campaigns - was inconsistent with the laws requiring use of seatbelts and child car seats and prohibiting cellphone use while driving.
• The Health Ministry is working on forcing tobacco retailers to be listed on a state register of tobacco outlets.
• This could provide a new penalty in the de-licensing of shops which illegally sell cigarettes to people under 18.
• New Zealand has up to 10,000 tobacco retailers.
• Other ongoing work includes looking at the prevention of smoking in cars containing children. Health officials are looking at tightening the regulatory net over retail sales of tobacco.