Sept 1 (Reuters) - Amazon's ⁠Zoox and Alphabet's Waymo on Tuesday separately announced ⁠expansions of their driverless ride-hailing operations into ‌new U.S. cities, weeks after Zoox started paid services.

Zoox said it would begin testing in Houston and San Diego, bringing its ​presence to 12 U.S. locations. It ⁠will initially use ⁠retrofitted test vehicles for manual mapping and testing before ⁠deploying its ‌purpose-built driverless robotaxis.

Its commercial launch has intensified competition with Waymo and Tesla as ⁠companies race to scale autonomous ride-hailing in the ​U.S.

Waymo, meanwhile, ‌said it would begin welcoming its first public ⁠riders in ​Denver, San Diego and Tampa, bringing its fully autonomous ride service to 14 cities. The company said it ⁠would gradually expand access to ​riders in the three cities.

Zoox has been carrying passengers for free in Las Vegas, San Francisco, Austin and ⁠Miami as part of its testing program, before it started offering paid rides in Las Vegas in August.

Waymo already operates paid driverless services in multiple U.S. ​cities and is also expanding ⁠overseas. The company said last month it would begin ​testing in Munich ahead of ‌a planned commercial launch in ​Germany toward the end of 2027.

(Reporting by Anzar Mehraj in Bengaluru; Editing by Sahal Muhammed)