The Trump administration will move on Monday to sharply scale back fuel-efficiency rules for new cars and light trucks, gutting one of the government’s most significant efforts to reduce gasoline consumption and speed the country’s shift to electric vehicles.
President Trump said on Saturday on social media that he had “just approved new Fuel Economy Standards,” adding falsely that President Joseph R. Biden Jr. had implemented an “E.V. mandate.” The transportation secretary, Sean Duffy, said in his own social media post that the move would be announced Monday.
The final rule from the Transportation Department is expected to significantly weaken federal mileage standards, which have prodded automakers to increase the fuel efficiency of gasoline-powered cars and to sell more nonpolluting electric models.
The proposed rule, issued in December, required automakers to achieve an average fuel efficiency of 34.5 miles per gallon for cars and light trucks in model year 2031, down from the standard of 50.4 miles per gallon set by the Biden administration.
Mr. Trump claimed on social media that loosening the mileage standards would lower the price of new cars by thousands of dollars. But Congress already eliminated fines for automakers that don’t meet the standards, rendering the rollback on Monday largely symbolic.
At the same time, drivers across the country have been spending more on gas since the U.S.-Israeli attacks on Iran began in February. The national average price of a gallon of gas was $4.48 on Saturday, according to the AAA motor club.