The new government will repeal the law that would have barred the sale of cigarettes to anyone born after 2009, among other measures.
National's coalition deal with New Zealand First says it will repeal amendments to the Smokefree Environments and Regulated Products Act 1990 and regulations before March 2024
These changes would remove requirements for denicotisation and remove the reduction in retail outlets and the generation ban, while also amending vaping product requirements and taxing smoked products only. Under the coalition, National could no longer fund its promised tax cuts through a tax on foreign buyers, and had to look elsewhere for revenue.
University of Auckland professor Chris Bullen, president of the international Society for Research on Nicotine and Tobacco (SRNT), said New Zealand's legislation had inspired other countries to look at similar policies.
SRNT is the world's largest scientific society that researches tobacco smoking and nicotine, and its membership includes more than 1300 scientists from around 40 countries.
As its president, Bullen says he is in "regular contact with many of the world's leading scientists, across the world, who have devoted their careers to researching about the harms of tobacco smoking, the science of nicotine addiction and so forth".
"They were truly in awe of our position, [saying] 'we wish we could be where you were'. Now they have universally come out in shock, and they're offering support, asking, 'How can we help, can we write to your Prime Minister?' and indeed a number of them have, just to see if the government would change its mind."
Martin McKee from the London School of Hygiene and Tropical Medicine told RNZ that reversing the smokefree laws to fix a tax cut funding problem was inexplicable.
Bullen said New Zealand's reputation in the international public health space was "now pretty tarnished".
"It just really speaks to the influence of the tobacco industry on our political leadership and the fact they're prepared to swallow their so-called evidence ahead of well-established, international and local scientific support and evidence."
He said New Zealand had "really occupied first place in the world in terms of best practice with our plans to roll out these strategies that were articulated in the act ... it was inspiring to many other countries and it showed what might be possible. Good research-informed policy making and it looked like New Zealand was leading the charge and would inspire other countries to take decisive action.
"But this no longer seems to be the case, and we're all feeling a bit deflated and embarrassed after this complete about-turn of events."
Minister of Health Dr Shane Reti has defended the National-led government's plans to repeal smokefree legislation, telling RNZ's Checkpoint programme this week it was "absolutely committed to reducing smoking rates".
Vaping had made a significant contribution to reducing adult smoking rates and it remained the main tool for a smoking rate that was slowly but surely improving, he said.
"I am pleased, as we should all be, with the adult smoking rate reduction, but we all want to do more, we're all committed to reducing the smoking rates in New Zealand and I remain committed to that."