The letter comes after the state of California suspended the permit of General Motors Cruise robotaxi to test on public roads following an Oct. 2 accident involving a pedestrian that was dragged 20 feet by a self-driving vehicle.

"The AV industry is at a critical juncture and in need of strong leadership from USDOT," said the letter signed by the Autonomous Vehicle Industry Association, U.S. Chamber of Commerce and others. "The department's support for AV development is crucial to maintain our nation's competitive edge."

(Reporting by David Shepardson)