Strong sales of pickups and sport utility vehicles are keeping national fuel economy at a 20-year low, the US government says, according to a report from Associated Press (AP).

The focus on bigger, more powerful vehicles led to the Environmental Protection Agency finding that average gasoline mileage for 2000 model year passenger vehicles was 24 miles per gallon, the same as 1999 and the lowest since 1980. The figure had climbed to 25.9 mpg in 1987 and 1988, AP said.

The drop in fuel economy corresponds to a surge in sales of "light trucks," which include vans, pickup trucks and sport utility vehicles and account for 46 percent of all US passenger vehicle sales.

The average 2000 car gets 28.1 mpg, while light trucks get 20.5 mpg.

“Consumers want cars that have certain performance features," Gloria Bergquist, spokeswoman of the Alliance of Automobile Manufacturers that lobbies on behalf of 13 automakers, told AP.

But Dan Becker, director of the Sierra Club's global warming program, said on Tuesday that better gas mileage would reduce oil consumption, lower fuel costs and lower carbon dioxide emissions.

AP says that the EPA report, published last week, said new technologies on the market could increase fuel economy, but automakers are focused on building heavier vehicles and increasing acceleration.

Ford and GM announced last summer that they would increase the fuel economy of its SUV fleet by at least 25 percent by the 2005 model year.

The EPA report also said that if all the automakers increased their passenger vehicle fleets' gas mileage by 25 percent, average fuel economy would increase to 30 mpg, AP reported.