The Trump administration is expected to release a plan this week that halts tightening fuel efficiency standards and revokes California’s unique ability to impose stricter air pollution controls. The move aims to undo some of the top tools in the US for combating climate change promoted by former president, Barack Obama.

Bloomberg reported July 23 that the federal government is planning to freeze vehicle-emissions standards at its 2020 targets through 2026. That would cap fuel economy requirements at 35-miles-per gallon (mpg) rather than 50 mpg for all vehicles in 2025, as laid out during Obama’s presidency.

The White House will also seek to revoke California’s special waiver from the US Environmental Protection Agency that allows the state to set stricter air-pollution rules than those imposed nationwide under the 1970 Clean Air Act. Since then, California has been able to operate its own, stricter regulatory scheme to dramatically cut pollution levels in cities such as Los Angeles. (Many of the most smog-ridden cities in the US are in California.)

California also led the nation by requiring automakers to cut greenhouse gas emissions from vehicles with 2004 regulations (pdf) to slow global warming. The new rules mean the state, which accounted for 2 million in new car sales last year, would lose its role as the trendsetter for reducing emissions nationwide. (Even China modeled its own program to boost zero-emission vehicles on California’s).

The changes would likely benefit car companies that will no longer be forced to build more efficient vehicles for Californian standards, but cost buyers dearly. The energy consultancy Rhodium Group estimated drivers will pay $193 billion extra for gas through 2035, while contributing volumes of greenhouse gasses equivalent to opening 28 new coal plants, The Atlantic reported.