New Zealand should ban all tobacco, or at least regulate the hundreds of additives that go into a cigarette to make smoking a foul-tasting and "retching" experience, says tobacco company whistle-blower Jeffrey Wigand.

Such moves would be world-leading and make major progress towards a smoke-free New Zealand by 2020, he told the Maori affairs select committee yesterday.

Dr Wigand, the former vice-president of research and development at tobacco company Brown & Williamson, said there were two types of additives in cigarettes: those that made it tasty, and those that enhanced the delivery of nicotine.

"What really makes tobacco palatable is the additives. Take the additives out of the product and the product is no longer desirable ...

"If you truly want to have New Zealand tobacco-free by 2020, you have to make this a hostile environment for the tobacco industry, and you do that by regulating."