WASHINGTON — The Trump administration says people would drive more and be exposed to increased risk if their cars get better gas mileage, an argument intended to justify freezing Obama-era toughening of fuel standards.

Transportation experts dispute the arguments, contained in a draft of the administration’s proposals prepared this summer, excerpts of which The Associated Press obtained.

The excerpts show the administration plans to challenge California’s long-standing authority to enact its own, tougher pollution and fuel standards.

Revisions to the mileage requirements for 2021 to 2026 are still being worked on, the administration says, and changes could be made before the proposal is released as soon as this week.

The Trump administration gave notice earlier this year it would roll back tough new fuel standards put into place in the waning days of the Obama administration. Anticipating the new regulation, California and 16 other states sued the Trump administration in May.

Overall, “improvements over time have better longer-term effects simply by not alienating consumers, as compared to great leaps forward” in fuel efficiency and other technology, the administration argues. It contends that freezing the mileage requirements at 2020 levels would save up to 1,000 lives per year.

New vehicles would be cheaper and heavier if they don’t have to meet more stringent fuel requirements and more people would buy them, the draft says, and that would put more drivers in safer, newer vehicles that pollute less.

David Zuby, chief research officer at the Insurance Institute for Highway Safety, said he’s doubtful about the estimate of lives saved because other factors, such as automakers agreeing to make automatic emergency braking standard. “They’re making assumptions about stuff that may or may not be the same,” he said.