The administration's final rule relaxes future mileage standards for years to come, gutting tougher Obama-era standards that were the U.S. government's single most forceful initiative against climate-changing fossil fuel emissions.
"Great news! American families will now be able to buy safer, more affordable, and environmentally friendly cars with our new SAFE VEHICLES RULE," President Donald Trump declared in a tweet. "Get rid of those old, unsafe clunkers. Build better and safer American cars and create American jobs. Buy American!"
But Democratic lawmakers and environmental groups condemn the rollback, and years of legal battles are expected, including from California and other states opposed to the rollback.
The rollback drew rare public criticism from former President Barack Obama, who largely has remained silent as his successor targets public health, environment and climate regulations from Obama's time as part of the current administration's regulation-cutting drive.
"We've seen all too terribly the consequences of those who denied warnings of a pandemic. We can't afford any more consequences of climate denial," Obama tweeted after Trump's transportation and Environmental Protection Agency heads made the final rule public.
Obama also ventured into this year's presidential campaign with the mileage rollback, telling Americans to ""vote this fall."" His vice president, Joe Biden, is the front-runner for the Democratic presidential nomination.
Trump's new mileage standards will require automakers to achieve 1.5% annual increases in fuel efficiency. That's less than the more than 2% increases the U.S. auto industry is already averaging.
John Bozzella, CEO of the Alliance for Automotive Innovation, a trade group representing automakers, said the industry still wants middle ground between the two standards, and it supports year-over-year mileage increases. But he says the Obama-era standards are outdated because of the drastic shift to trucks and SUVs.
Trump initially proposed simply dropping mandates for more fuel efficiency entirely, but he compromised after California and a dozen other states and a faction of automakers revolted, and after Trump federal officials had difficulty coming up with justifying arguments.
