National says the electric vehicle discount and high-emitter fee, both proposed today by Government, would unfairly penalise people struggling with the cost of living and would also impact farmers and tradies.
The discounts and fees would apply to new and used cars sold in New Zealand for the first time and would begin in 2021.
National MP Brett Hudson said popular new imported cars would see a "significant price hike".
"Hiking the cost of certain vehicles will also impose more costs on some families who still can’t afford to switch to an electric vehicle," he said.
"Vehicle emissions are one of the biggest contributors outside of agriculture, so we need to work on reducing them, but doing so shouldn’t come at the expense of New Zealanders’ wellbeing by increasing the cost of living further."
He said there were also questions around "farmers and tradies who don't necessarily have the ability to shift into lower emission vehicles, given suitable options for their lifestyle just don't exist".
Federated Farmers Vice President Andrew Hoggard said the proposal had "probably been thought of in an urban sense".
"Unless there is an electric vehicle that can take a whole lot of fencing equipment, kids, whole bunch of supplies and the groceries, we're kind of stuck with that double cab ute," he said.
Associate Transport Minister Julie Anne Genter said the policies were about "making it a more realistic option for more New Zealanders to get a car that is better for the climate and will also save them money".
She said it would "eventually" make electric vehicles accessible to the average New Zealander.
"The more new vehicles we bring in that are electric, the more that will filter through to second hand here in New Zealand."
When asked why it did not apply to resale within New Zealand, Ms Genter said "it makes sense to start with cars at the point they are coming into New Zealand and that's how we can do this in a gradual way".
Greenpeace said in a statement today the proposal was a good first step, "but needs more drive to tackle the climate emergency".
Climate and energy campaigner Amanda Larsson said New Zealand had been one of the few developed countries without vehicle emissions standards.
"We need to follow in the footsteps of many of our European counterparts by putting a time limit on petrol and diesel vehicles, and committing to phasing out imports by 2030."
New plug-in hybrids, that run on petrol and electricity, would see a $6800 discount, new fuel efficient cars would get a $2800 discount and used imported electric cars would save $2600.
High emission Range Rovers and the Nissan Patrols would be hit with a $3000 fee.
The new rules would also apply to car importers, having to reduce the average emissions of the vehicles imported each year.