The outgoing administration of President Joe Biden is finalizing rules that would ban virtually all Chinese cars and trucks from the US market as part of an effort to crack down on the expansion of vehicle software and hardware from China.

Washington’s latest move against Chinese vehicles comes after the Commerce Department said this month it was considering a similar crackdown on Chinese-made drones in the wake of last year’s sharp tariff increases on imports of its electric vehicles, Reuters reports.

“It’s really important because we don’t want two million Chinese cars on the road and then realize we have a threat,” Commerce Secretary Gina Raimondo told Reuters, citing national security concerns.

In September, the US Commerce Department proposed a sweeping ban on key Chinese software and hardware in connected vehicles on US roads, with bans on software starting in the 2027 model year and those on hardware in 2029. It also bans Chinese car companies to test self-driving vehicles on US roads.

The rules also cover Russian vehicles and accessories.

The U.S. Commerce Department announced that it made some changes to the final rules, including a special vehicle exemption that would allow China’s BYD to sell electric buses in California.

The Alliance for Automotive Innovation, representing the GM, Toyota Motor, Volkswagen, Hyundai Motorand other major automakers, failed to secure an extra year for automakers to meet the new hardware requirements.

Polestar, the Swedish automaker that is a subsidiary of China’s Geely, warned in October that without changes to the new regulations it would be “effectively barred” from selling vehicles in the United States.

In September, the Biden administration ended steep tariff increases on Chinese electric vehicle imports and this month placed key Chinese battery company CATL on a list of companies accused of aiding China’s military.

President-elect Donald Trump, who takes office on Jan. 20, wants to prevent Chinese auto imports but is open to Chinese automakers making vehicles in the United States.