Anti-smoking researchers are promising a healthy fight against the new government's moves to repeal world-first legislation on tobacco sales.

Health professionals and smokefree experts universally expressed disbelief over the new government's moves to roll back dramatic moves aimed at reducing New Zealand's tobacco harm - and they say they'll fight the decision.

Approximately 9 percent of New Zealanders smoke tobacco, down from around 20 percent when Smokefree 2025 targets were put in place in 2011.

The decision that's shocked the health sector was hidden away as the 16th bullet point on page eight of the 15-page New Zealand First coalition agreement, and also on page eight (as the 21st bullet point) on ACT's agreement.

Labour's world-beating, globally-lauded amendments to our Smokefree legislation are set to be repealed.

The amendments would have taken cigarettes out of most dairies, lowered the nicotine levels in ciggies, and denied sales to anyone born after January 1 2009.

After years of continual tax and excise increases that have gradually cut the number of smokers, this would have been a sea change that introduced a smokefree generation.

National's variously said that the move was at the behest of its coalition partners and that it would have driven up crime, with gangs getting in on black market cigarettes.

Willis also let slip that the revenue from tobacco sales would also help plug National's funding gap for its promised tax cuts.

In an interview with Newshub Nation, finance minister Nicola Willis admitted scrapping Smokefree laws would plug the fiscal gap left by National's proposed foreign buyer tax, which fell out of favour in coalition negotiations.

The tax on a packet of cigarettes is about 70 percent of its price, and the total tax revenue generated by tobacco is about 1.1 percent of total tax revenue, according to estimates by the New Zealand Initiative.

New Zealand First's pre-election literature had described the country's Smokefree 2025 aim as "illusory" - ACT's main objection was the crime angle.

Health academics and researchers all reached for the same words to describe how they felt about the move - "unbelievable" and "beyond belief".

Today on The Detail we speak to Professor Chris Bullen from the school of population health at the University of Auckland. He's a public health physician who's been researching, teaching and thinking about smoking-related issues for 20 years.

And he's a big backer of our Smokefree legislation.

When he heard the repeal news, "I felt like buying a one way ticket out of New Zealand," he says. …

Go to this episode on rnz.co.nz for more details