SAN FRANCISCO (KRON/AP) — Uber has pulled self-driving cars off California roads, says state revoked registrations.

The ride-sharing company said Wednesday that California transportation regulators revoked registrations for the vehicles.

Hours after Uber launched the service in San Francisco, the Department of Motor Vehicles demanded it stop until the company got a special testing permit to run on public roads.

Uber argued that the cars weren’t technologically advanced enough to require a permit under state regulations.

Back-and-forth talks over the past week couldn’t bridge the gap.

An Uber spokeswoman has issued the following statement to KRON4:

“We have stopped our self-driving pilot in California as the DMV has revoked the registrations for our self-driving cars. We’re now looking at where we can redeploy these cars but remain 100 percent committed to California and will be redoubling our efforts to develop workable statewide rules.”

The DMV confirmed that it had moved to revoke the registrations of 16 cars, saying officials had been determined that the registrations were improperly issued because the vehicles were not properly marked as test vehicles.

The California Department of Motor Vehicles released this statement:

Consistent with the department’s position that Uber’s vehicles are autonomous vehicles, the DMV has taken action to revoke the registration of 16 vehicles owned by Uber. It was determined that the registrations were improperly issued for these vehicles because they were not properly marked as test vehicles. Concurrently, the department invited Uber to seek a permit so their vehicles can operate legally in California.

California’s testing regulations for autonomous vehicles strikes a balance between protecting public safety and embracing innovation. These regulations were adopted two years ago, and they are working for the 20 manufacturers now testing more than 130 autonomous vehicles on California’s streets and roads. Uber is welcome to test its autonomous technology in California like everybody else, through the issuance of a testing permit that can take less than 72 hours to issue after a completed application is submitted. The department stands ready to assist Uber in obtaining a permit as expeditiously as possible.