The coalition's pledge to put the brakes on fines for high-polluting vehicles has split the automotive industry, with some groups arguing it would halt progress on emissions while others called it a necessary overhaul.
Opposition leader Peter Dutton announced proposal on Friday, revealing an elected coalition government would scrap financial penalties under Australia's New Vehicle Efficiency Standard.
The law, which sets emissions standards for new passenger and heavy vehicle fleets, came into effect in January but penalties and credits were not due until July this year.
Electric vehicle groups slammed the move, saying stripping fines would be like setting "road rules without enforcement," while some motoring bodies said the change should be part of a wider remodelling of the scheme.
Under the proposal, the coalition would remove potential fines for car companies that exceed annual emission limits set for their new car fleets.
Penalties issued under the scheme would raise the price of new vehicles including popular utes, Mr Dutton said, adding to the cost of living.
"We want vehicle emissions standards to be responsible," he said.
"Of course we want cleaner fuel but I want Australians to be able to afford to live."
AAP FactCheck recently analysed claims the standards would drive up vehicle costs, finding false claims had been made based on outdated figures.
Penalties would not necessarily drive up the purchase price of cars, it found, as fines were based on a manufacturer's total fleet sales.
The opposition has also announced plans to halve petrol excise for 12 months to reduce petrol by 25 cents per litre.
But Prime Minister Anthony Albanese said removing penalties from the vehicle standard would also remove incentives for companies to bring efficient cars to Australia.
"We have not put an allocation of an expectation of any revenue from this measure in terms of so-called fines," he told reporters.
"What it is doing is making sure that Australians get cheaper vehicles."
Without emission limits and repercussions for breaking them, automakers would not deliver their most fuel-efficient models to Australia and consumers would miss out like they had done in the past, Electric Vehicle Council chief executive Julie Delvecchio said.
"The (standard) doesn't work without the credit and penalty system," she said.
"Removing fines from the NVES is like having road rules without enforcement – no consequences for breaking the rules and no motivation to follow them."
Changing the standard would also remove "the reward for those doing the right thing," Australian Electric Vehicle Association national president Chris Jones said.
But some motoring groups welcomed the coalition's announcement, including the Caravan Industry Association and the Federal Chamber of Automotive Industries that represents more than 60 vehicle brands.
The supply of electric and hybrid vehicles was no longer constrained in Australia, chamber chief executive Tony Weber told AAP, and the standard should be overhauled and emission limits renegotiated to be more "achievable".
"Fines don't actually meet the policy objective, in my mind," he said.
"Fines will just put more cost pressure into the system and that cost pressure will ultimately be borne by consumers."
Australia had been one of just four major countries without a fuel-efficiency standard before the laws were introduced this year, alongside Russia, Turkey and Indonesia.
