The government has watered down standards aimed at improving the fuel efficiency of New Zealand's new cars, saying the current schedule is too strict for car importers.
Transport Minister Simeon Brown said the new standards would be the same as Australia's, because the two countries were effectively one car market.
Australia's standards were also watered down from what was originally proposed, after lobbying from the petrol and diesel car industry that the changes went too far.
The Clean Car Standard limits the average carbon dioxide emissions from the tailpipes of new cars brought into the country. It was introduced to lower emissions and avoid New Zealand being a dumping ground for less efficient vehicles which could not be sold in territories with stricter rules.
However, the minister said the standards for 2025-2029 would be increasingly difficult for importers to meet and would cost car buyers thousands per vehicle in upfront costs.
Clean car advocates saw the changes coming when the government moved to pass the Land Transport (Clean Vehicle Standard) Bill through Parliament under urgency, repealing Clean Car targets and allowing the minister of transport to set new ones.
Drive Electric, a clean car lobby group, said weakening standards would only lead to people being locked into higher petrol and diesel bills for decades to come.
It said "only a handful of players" had been talked to before making the move - and if New Zealand was aligning its standards with Australia's, it should also copy Australia's 'comprehensive' incentives to buy EVs.
Average tailpipe carbon pollution from new cars entering New Zealand has risen since the government scrapped subsidies for buying EVs, and lobbyists say the Clean Car Standard is the one remaining tool for shifting towards a cleaner fleet.
"The fleet is already getting dirtier and now we're weakening emissions standards," a statement from Drive Electric said.
Brown said the government supported the Clean Car Importer Standard and the changes followed a "comprehensive review".
Advice provided to him by the Ministry of Transport found that under current targets, penalties for importers were forecast to amount to about $800.6 million of cost to consumers purchasing a new car in 2027 or about $5549 per vehicle, he said.
"The review found that the Standard's current targets are too stringent and are increasingly difficult for importers to meet, as they are out of step with manufacturing standards from leading vehicle manufacturers. In fact, the review found that the commercial targets for 2026 and 2027 are more stringent than every other country in the world," said the minister's statement.
Following the current path would add costs to consumers without cutting emissions, he said.
"These changes will ensure the Standard emissions targets are stringent enough for New Zealand to receive a supply of clean vehicles, but not too stringent that importers cannot meet the targets, leading to higher vehicle prices," Brown said.
RNZ has asked the minister's office for a copy of the Ministry of Transport's advice.