The Obama administration said Monday it was considering seeking the power to review and approve technology for self-driving cars before they hit the road and said U.S. states should not set separate rules.

The U.S. Transportation Department, in its most comprehensive statement yet on autonomous vehicles, also issued voluntary guidelines and urged automakers to certify that their highly automated vehicles were ready for public roads.

“If a self-driving car isn’t safe, we have the authority to pull it off the road. We won’t hesitate to protect the American public’s safety,” President Barack Obama wrote in a Pittsburgh Post-Gazette op-ed published Monday. “We have to get it right.”

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Automakers and technology companies are racing to develop vehicles that can drive themselves at least part of the time. They have complained that state and federal safety rules impede the process.

Obama wrote the administration is asking automakers “to sign a 15-point safety checklist showing not just the government, but every interested American, how they’re doing it.”

The guidelines include testing, backup systems in the case of a self-driving computer failure, and recording and sharing data. Companies would also have to demonstrate how vehicles would comply with all traffic laws and fare in traffic crashes and how they would perform after a crash.

The government currently allows automakers to self-certify that vehicles comply with safety standards.

U.S. Transportation Secretary Anthony Foxx said on a conference call with reporters that a new premarket approval system overseen by the government would “would require a lot more upfront discussion, dialogue and staffing on our part.”

The National Highway Traffic Safety Administration has been investigating Tesla Motors’ (TSLA) Autopilot system since June because of a May 7 fatal crash in Florida in which the system was in use. The Autopilot system, which allows drivers to keep their hands off the wheels for extended periods, did not require any pre-approval by the agency for use by owners.

On another issue, the administration’s guidance sides with Alphabet’s Google (GOOG) unit by calling for the federal government, not states, to set the rules governing vehicles driven by computers.

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Google criticized California last year when the state proposed draft rules requiring steering wheels and a licensed driver in all self-driving cars.

A person briefed on the guidelines prior to their release on Tuesday said they urge states not to require the presence of a licensed driver in the driver seat when a highly automated vehicle is in operation. The person requested anonymity because the guidelines had not yet been made public.

“When a human being is operating that vehicle, the conventional rules of state law would apply,” Foxx told reporters on a conference call on Monday. The goal is to “avoid a patchwork of state laws,” he added.

The California Department of Motor Vehicles said in a statement on Monday that it would not comment until it saw the guidelines, but said it planned to release revised draft regulations in the coming weeks.

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The state of Michigan, in contrast, is moving to adopt legislation to no longer require a licensed driver in a self-driving car while testing on public roads.

The Self-Driving Coalition for Safer Streets, whose members include Google, Ford Motor Co. (F) and ride-hailing service Uber, said in a statement they hoped policymakers could develop a framework that avoids a “patchwork of requirements that could inhibit self-driving vehicle development.”

Gloria Bergquist, a spokeswoman for the Alliance of Automobile Manufacturers, a trade group representing major automakers, said in a statement that the government’s goal should be to “avoid policies that become outdated and inadvertently limit progress in reducing the number of crashes and saving lives.”