WASHINGTON, - U.S. auto safety investigators asked Tesla to answer questions on the automaker's plans to launch a paid robotaxi service in Austin, Texas, in June to assess how it will perform in poor weather.

The National Highway Traffic Safety Administration in a letter made public Monday noted it has an ongoing investigation into Tesla Full-Self Driving collisions in reduced roadway visibility conditions.

NHTSA said it is seeking additional information about Tesla's development of robotaxis "to assess the ability of Tesla's system to react appropriately to reduced roadway visibility conditions."