U.S. President George W. Bush signed into law Wednesday legislation that increases the federal auto mileage requirement for the first time in 32 years and also ramps up the use of ethanol as a gasoline substitute.

U.S. President George W. Bush signs the Energy Independence and Security Act on Wednesday in Washington, while House Speaker Nancy Pelosi and Senate Majority Leader Harry Reid applaud.
(Charles Dharapak/Associated Press)

Under the new legislation, motor vehicles will be required to meet an average 35 miles per U.S. gallon (6.7 L/100 km) by 2020.

"We make a major step … toward reducing our dependence on oil, fighting global climate change, expanding the production of renewable fuels and giving future generations … a nation that is stronger, cleaner and more secure," Bush said at the Energy Department ceremony.

The U.S. Congress sent the legislation to the White House late Tuesday — delivering it in a gas-hybrid sedan — after it was passed by majorities in both houses.

Democrats said the legislation represents a turn away from fossil fuels to using more renewable energy sources and put greater emphasis on conservation.

But some Republicans complained the legislation fails to address the need for more domestic production of fossil fuels, especially oil and natural gas.

With files from the Associated Press