Associate Health Minister Tariana Turia has admitted it may be too hard to ban smoking in cars.
Ms Turia has asked the Ministry of Health to look at the options around banning smoking in cars, but she says it might be too difficult to police.
She's suggesting self-policing could be an alternative.
"One of the ways we could do that is to encourage people who see people smoking in cars tooting to them," Ms Turia said.
Ms Turia is a strong supporter of action on smoking and the Maori Party co-leader wants to ban smoking in cars to help it get to its goal of New Zealand being smokefree by 2025.
The government announced a hike in tobacco tax of 10 per cent each year for the next four years in last week's budget, taking the price of a pack of cigarettes to around $20 by 2016.
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