The US Department of Commerce has finalized a rule banning the sale and import of connected vehicles from China and Russia due to national security concerns.

Announced on Thursday, the rule also prohibits Chinese companies from testing self-driving cars on US roads.

The ban will take effect in stages, starting with software in 2027  model year and hardware in 2029.

However, earlier versions of Chinese-developed software will remain allowed if companies have no access to it.

An exemption allows Chinese automaker BYD to continue assembling electric buses in California.