WASHINGTON -- The National Highway Traffic Safety Administration and automobile manufacturers will join forces to fight a congressional push for increased fuel efficiency standards for vehicles, lobbyists and administration officials say.

The standards, known as Corporate Average Fuel Economy (CAFE), haven't been boosted since 1985, when auto makers were required to attain a 27.5 mile-per-gallon rating.

But the Persian Gulf crisis intensified public concern over energy conservation and has caused Congress to consider raising CAFE standards again. Various bills call on manufacturers to hit at least 40 miles per gallon by the turn of the century.

Public Citizen, a public interest organization founded by consumer advocate Ralph Nader, claims that average fuel efficiency could have been 33.4 miles per gallon in 1990, instead of 28.1 miles per gallon, had consumers chosen the most fuel efficient cars in their size classes.

"Manufacturers have ignored fuel economy, absent real pressure from the government, and have moved to put bigger engines in their cars," said Public Citizen President Joan Claybrook.

But opponents of the raised CAFE ratings say current technology can't comply with the proposed standards by the next decade.

If the standards are raised, manufacturers will have to downsize their models to meet government regulations, they say.

"The problem is that customers don't want small cars, They don't sell well," said Mike Stanton, a lobbyist with the Motor Vehicle Manufacturers Association.

In reaction, consumers either would use two cars for trips that now require only one vehicle or they would hang on to larger, gas-guzzling vehicles. Both tactics defeat the CAFE intentions, automobile industry lobbyists say.

Jerry Curry, administrator of the National Highway Traffic Safety Administration, said he "strongly opposes" higher fuel efficiency standards, arguing that smaller cars are more dangerous, particularly since large vehicles remain on the roads.

"When does fuel conservation become more important than saving American lives? . . . There were people who would be alive today if, in our zeal to save gas, cars had not been so drastically stripped of weight," Curry said.