Tesla CEO Elon Musk said in a post on X that the limited, invitation-only service that began June 22 will be open to all comers sometime in September.

Guggenheim analyst Ronald Jewsikow said the move is a key step toward expanding Tesla's full self-driving model into a broader Robotaxi fleet. Tesla shares have fallen 16% year to date but edged less than 1% higher in premarket trading Tuesday.

Tesla's ( NASDAQ: TSLA) robotaxi service in Austin will be open to the general public starting in September, according to a social media post by CEO Elon Musk. The public launch will follow an initial invite-only phase that began in June with a limited group of users and a small fleet of driverless vehicles.