President Donald Trump announced a new plan that lets carmakers pollute more by making less fuel efficient vehicles. The National Highway Traffic Safety Administration (NHTSA) said today that it’ll roll back fuel economy rules finalized last year by the Biden administration for model year 2022-2031 vehicles.

The Trump administration has eliminated incentives for EV purchases, stymied energy efficiency policies and gutted pollution regulations in general. The president wants the US to produce more oil and gas, and says that his agenda will boost business for American automakers. Critics contend that Americans will ultimately pay for these measures with higher fuel costs, as well as health risks and climate disasters stemming from tailpipe emissions.

“Slashing fuel economy standards will increase costs for drivers and threaten the progress made in reducing dangerous air pollution and preventing adverse health outcomes for children, older adults, and communities who live near busy roads,” Darien Davis, government affairs advocate on climate change and clean energy at the League of Conservation Voters, said in a statement emailed to The Verge.

NHTSA proposed a federal fuel economy standard of around 34.5 miles per gallon of gas by 2031. That’s far lower than the bar Biden set last year of reaching an average of roughly 50.4 miles per gallon by 2031.

The agency previously estimated that the higher standards set in 2024 would collectively save Americans $23 billion in fuel costs over the years, or about $600 for each passenger car and light truck owner over the lifetime of their vehicle. The rules were expected to cut down gasoline use by 70 billion gallons through 2050. That would avoid 710 million metric tons of planet-heating carbon dioxide pollution, equivalent to taking more than 165.6 million gas-guzzling passenger vehicles off the road for a year. Trump claimed without evidence that his latest action would shave $1,000 off the price of a car, while clean energy advocates expect the rollback to lead to higher fuel costs.

GM had paid $128.2 million in CAFE penalties for 2016 and 2017, Reuters reports. Stellantis, which owns Chrysler, has paid more than $590 million in penalties since 2016. Leadership for both companies joined the president in the Oval Office today as he announced the new CAFE standards.

“We’ve just freed you up, so you’re going to have a good day, you’re going to have a good number of years,” Trump said to auto industry leaders during the announcement.

“Today is a victory of common sense and affordability,” Ford CEO Jim Farley later responded.