WASHINGTON — The Obama administration on Tuesday introduced new rules to double fuel economy for cars and light-duty trucks by 2025, a move that the White House says will be comparable to cutting a dollar a gallon from the price of gasoline and that auto dealers warned would raise the cost of a new car.

WASHINGTON — The Obama administration on Tuesday introduced new rules to double fuel economy for cars and light-duty trucks by 2025, a move that the White House says will be comparable to cutting a dollar a gallon from the price of gasoline and that auto dealers warned would raise the cost of a new car.

The new rules boost fuel economy to the equivalent of 54.5 miles per gallon over the next 13 years, building on the White House's existing effort to raise fuel economy to 35.5 mpg by 2016. The new rules are aimed at prodding manufacturers to make more fuel-efficient cars even as the standards lower fuel consumption and dramatically curb greenhouse gas emissions.

"These fuel standards represent the single most important step we've ever taken to reduce our dependence on foreign oil," President Barack Obama said in a statement. "By the middle of the next decade our cars will get nearly 55 miles per gallon, almost double what they get today. It'll strengthen our nation's energy security, it's good for middle-class families, and it will help create an economy built to last."

Republican presidential candidate Mitt Romney has said he opposes the new standards and doesn't believe it's the right approach to have manufacturers meet them by building cars consumers don't want.

New-car dealers support continuous fuel economy increases, said Bill Underriner, chairman of the National Automobile Dealers Association. But they remain concerned that the new rules, coupled with the administration's previous fuel economy regulations, will raise the average price of a new vehicle by as much as $3,000.

"This increase shuts almost 7 million people out of the new-car market entirely and prevents many millions more from being able to afford new vehicles that meet their needs," Underriner said. "If this rule suppresses new vehicle sales, achieving the nation's greenhouse gas and energy security goals will be needlessly delayed."