Two self-driving cars from two different companies nearly collided with each other on the streets of Palo Alto, Calif., raising concerns over the safety of the technology.

A self-driving Lexus operated by Google apparently cut off a self-driving Audi controlled by Delphi Automotive during an attempt to change lanes, which caused the vehicle to take "appropriate action" in order to avert a collision, a Delphi executive said, The Washington Post reported. 

The close call took place on Tuesday on San Antonio Road in Palo Alto, said John Absmeier, director of Delphi's Silicon Valley lab and global business director of the company's self-driving program, who was a passenger in the company's automated vehicle at the time, Reuters reported.

Google released a report last month which revealed that its self-driving cars had 11 minor accidents since the inception of the program in 2009. Program director Chris Urmson said none of the self-driving cars were responsible for the accident, and many of the incidents involved the car being rear-ended by another vehicle, according to The Guardian.

Delphi Automotive, a self-driving startup, also reported an accident involving one of its automobiles last year, when its self-driving vehicle was broadsided by another car as it was waiting to make a left turn. Even though the Delphi vehicle was not in self-driving mode at the time, the company was still required to report the incident as per state law.