Alphabet-owned Waymo obtained a permit to start testing its robotaxis at San Francisco International Airport, San Francisco Mayor Daniel Lurie and the company announced on Tuesday.

Waymo will partner with the airport to roll out its commercial robotaxi service in phases, “beginning with employee testing soon ahead of welcoming Bay Area riders,” company spokesperson Chris Bonelli told CNBC.

That means the robotaxis will start with human drivers on board, ready to take control of the vehicles if needed, and eventually operate as a driverless ride-hail service.

Waymo is already operating its service in San Mateo County, where the airport is based, and in nearby San Francisco, but it does not yet have permission to ferry passengers to or from the airport.

In 2022, Phoenix Sky Harbor airport gave Waymo permission to test and operate its service there, and earlier this month, Waymo secured a permit to begin testing at San Jose Mineta International Airport.

Last month, Lurie said Waymo could operate a limited passenger service on one of San Francisco’s main thoroughfares, Market Street, where such services had previously been restricted.

For its general robotaxi service, Waymo now operates in Phoenix, parts of the San Francisco Bay Area, Los Angeles, Austin and Atlanta.

Tesla began testing a robotaxi service in Austin in June, with human safety supervisors on board. The Elon Musk-led company is also in discussions with San Francisco Bay Area airports. Tesla has permission to operate a paid car service in San Francisco, but not to run a driverless ride-hailing business there.

Tesla does not currently sell vehicles that are safe to use without a person in the car, ready to take over steering or braking at any time.

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