(Reuters) -Alphabet's self-driving unit Waymo said on Wednesday its vehicles will be back in New York City next month for autonomous testing, as it continues to scale operations in the U.S.

The race to deploy robotaxis is picking up pace as Waymo expands testing and Tesla prepares to begin limited trials of its autonomous taxi service with as few as 10 cars this weekend - a sign of growing momentum in self-driving vehicle development.

Waymo has applied for a permit from the New York City Department of Transportation to operate autonomously, with a trained specialist behind the wheel in Manhattan. 

"This is not an expansion, but we have every intention of bringing our fully autonomous ride-hailing service to the city in the future," Waymo said.

Waymo will start by manually driving in the city until it gets the permit. If granted, it would be New York City's first testing deployment of autonomous vehicles.

New York State law does not currently allow operating a vehicle with no human behind the wheel and Waymo said it is advocating for a change to the law.

The company had previously brought its cars to Manhattan in 2021 for manual driving, data collection and testing.

Waymo on Tuesday said it will expand into more areas of the San Francisco peninsula and parts of Silicon Valley. Last month, it received approval from California to expand operations.

As the only U.S. firm to run robotaxi services with paying passengers, Waymo has more than 1,500 vehicles, running over 250,000 rides a week across San Francisco and Los Angeles in California, Phoenix in Arizona and Austin in Texas.