Oakland, California - 2 August 2018

1. Exterior of Toyota car dealership

2. Various vehicles for sale inside dealership showroom

Washington DC – 2 August 2018

3. White House Press Secretary Sarah Sanders at briefing

4. SOUNDBITE (English) Sarah Sanders, White House Press Secretary:

"What the EPA (Environmental Protection Agency) released yesterday was a notice of proposed rule-making, not a final rule. The notice lays out a series of options for how to go forward with CAFE (Corporate Average Fuel Economy) standards. And the notice asks for comments on the range of options. We're simply opening it up for a comment period and we'll make a final decision at the end of that."

Los Angeles – 2 August 2018

5. California Attorney General Xavier Becerra listens to reporter's question at press conference at UCLA campus

6. SOUNDBITE (English) Xavier Becerra, California Attorney General:

"We intend to stand firm and protect the existing clean car standards that our nation has in place. And California will protect its waiver to continue to lead the fight to have cleaner air and cleaner-burning vehicles."

Oakland, California – 2 August 2018

7. Scientist Don Anair looking at Trump fuel efficiency proposal on laptop

8. Laptop screen shows fuel efficiency proposal

9. SOUNDBITE (English) Don Anair, Deputy Director of Clean Vehicles Program at Union of Concerned Scientists:

"Today the Trump administration proposed rolling back the most effective climate policy on the books of the United States. Essentially they decided to freeze fuel economy and emissions standards at 2020 levels, which will be bad for consumers, bad for oil and energy security, and bad for the environment."

10. Union of Concerned Scientists sign

11. SOUNDBITE (English) Don Anair, Deputy Director of Clean Vehicles Program at Union of Concerned Scientists:

"And what the Trump administration proposed today was essentially revoking the ability for California and these other states to set their own standards and to protect public health and the environment of their states."

12. Anair working on laptop in conference room

13. SOUNDBITE (English) Don Anair, Deputy Director of Clean Vehicles Program at Union of Concerned Scientists:

"So transportation, our vehicles, are one of the biggest problems to overcome to address climate change. And these standards is the number one tool that we have to do that."

14. Various of Toyota used car dealership in Oakland

Citing safety, the Trump administration on Thursday proposed rolling back car-mileage standards, backing away from years of government efforts to cut Americans' trips to the gas station and reduce unhealthy, climate-changing tailpipe emissions.

If the proposed rule becomes final, it could roil the auto industry as it prepares for new model years and weaken one of the federal government's chief weapons against climate change — regulating emissions from cars and other vehicles.

The result, opponents say, will be dirtier air and more pollution-related illness and death.

The proposal itself estimates it could cost tens of thousands of jobs — auto workers who deal with making vehicles more fuel efficient.

The administration also said it wants to revoke an authority granted to California under the half-century-old Clean Air Act to set its own, tougher mileage standards.

California and 16 other states already have filed suit to block any change in the fuel efficiency rules.

The proposal would freeze US mileage standards at levels mandated by the Obama administration for 2020, when the new vehicle fleet will be required to hit an average of 30 miles per gallon in real-world driving.

The proposed change, halting further improvement requirements, stakes its case on consumer choice and on highway safety claims challenged by many transportation experts.

The administration says waiving requirements for greater fuel efficiency would make cars and light trucks somewhat more affordable.

And that, it said, would get vehicles with the latest technology into the hands of consumers more quickly.

California is one of 16 states suing to block any changes proposed.