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President Trump has taken one of his strongest shots yet at California, as the White House on Thursday unveiled its proposal to throttle back President Barack Obama’s regulations on planet-warming vehicle tailpipe pollution — including a plan to revoke California’s right to set its own standard.

The administration’s proposal, jointly published by the Environmental Protection Agency and the Transportation Department, would roll back a 2012 rule that required automakers to nearly double the fuel economy of passenger vehicles to an average of about 54 miles per gallon by 2025. It would halt requirements that automakers build cleaner, more fuel-efficient cars, including hybrids and electric vehicles.

The new proposal would freeze the increase of average fuel economy standards after 2021 at about 37 miles per gallon, while challenging a legal waiver — granted to California under the 1970 Clean Air Act and now followed by 13 other states — that lets those states set more stringent pollution standards than the federal government’s.

Gov. Jerry Brown did not mince words in his response: “For Trump to now destroy a law first enacted at the request of Ronald Reagan five decades ago is a betrayal and an assault on the health of Americans everywhere,” he said.