Self-driving technology companies, including Waymo, Cruise and Uber, have suspended autonomous car testing that involves backup drivers, over coronavirus fears.

Alphabet's Waymo said on Tuesday it was temporarily suspending robotaxi services in Phoenix that require a backup driver, but added that fully automated services would continue. The company is also pausing self-driving tests in California.

General Motors Co unit Cruise said it had suspended operations and closed all San Francisco facilities for three weeks. The test operators will be fully-paid for any days they would have worked during this period.

Argo, a unit of Ford Motor Co, said it had paused its vehicle testing operations, but added it has not experienced any significant impact due to the coronavirus.

Toyota-backed Pony.ai said it had paused its public robotaxi service in Fremont and Irvine, California for three weeks, but the company is testing cars in the Chinese cities of Beijing and Guangzhou.

Uber Technologies also said it would temporarily halt its test track and on-road track testing of self-driving vehicles.