Washington ? Congressional Democrats reached a compromise late Friday to boost automobile fuel economy by 40 percent, clearing the way for a House vote probably next week on an energy bill that Democratic leaders would like to send to President Bush before Christmas.

The agreement came after House Speaker Nancy Pelosi reached an accord with Rep. John Dingell, D-Mich., a longtime protector of the auto industry that dominates his home state, to ease the effect of the new fuel economy requirements.

“A compromise has been reached on automobile fuel efficiency standards,” Dingell announced in a statement.

Automakers would be required to meet an industrywide average of 35 miles per gallon for cars and light trucks, including sport utility vehicles, by 2020, the first increase by Congress in car fuel efficiency in 32 years.

With oil prices hovering near $90 a barrel and gasoline above $3 a gallon, Democrats have been eager to send Bush a package of new energy measures.

But Democratic leaders were stymied over disagreement on the auto fuel efficiency issues as Dingell, the longest-serving member of the House and chairman of the Energy and Commerce Committee, insisted on some provisions to ease the transition for automakers.

Pelosi, D-Calif., said in a statement that the auto efficiency increases “will serve as the cornerstone” of the energy bill she intends to bring up for a vote next week.

Agreement among Democrats on the auto fuel economy issue was viewed as key to getting the bill passed by the Senate, where opponents are sure to launch a filibuster, requiring 60 votes to overcome.

Senate Majority Leader Harry Reid of Nevada called the agreement “good news” and said he hoped to take up the legislation quickly after the House acts.

Sen. Carl Levin, D-Mich., who strongly opposed the 35 mpg requirement when it passed the Senate in June, endorsed Friday’s compromise. It “will require new fuel economy standards that will be challenging for auto manufacturers,” he said in a statement. “(But) we got concessions on some of the most important issues.”

Under the agreement, the ability of carmakers to use production of flex-fuel vehicles that run on 85 percent ethanol to offset some of the fuel efficiency increases would be extended five years, to 2014. Also, the new standards would be set on the basis of vehicle weight, giving manufacturers greater flexibility to meet the requirements for SUVs and pickup trucks.