WASHINGTON - The Obama administration today plans to set tough standards for tailpipe emissions from new automobiles, establishing the first nationwide regulation for greenhouse gases.

It will also raise fuel-efficiency targets to 35.5 miles per gallon for new passenger vehicles and light trucks by 2016, four years earlier than required under the 2007 energy bill, sources close to the administration said.

The measures take significant steps forward for the administration's energy agenda by cutting greenhouse-gas emissions that contribute to climate change, and by easing U.S. dependence on oil, most of which is imported.

The administration is embracing standards stringent enough to satisfy California, which has been fighting for a waiver from federal law so that it could set its own guidelines, sources said.

The deal has been under negotiation since the early days of the administration. It represents a compromise among the White House, California, and the automobile industry, which has long sought national mileage standards but has waged an expensive legal battle against the California waiver.

The industry will get its national standard - but at the price of one that approximates California's targets. David McCurdy, president of the Alliance of Automobile Manufacturers, said the agreement would provide the industry with "clarity and predictability."

That predictability won't come cheaply. A senior administration official said the new standards would increase the cost of an average car by $1,300 - $600 of which is attributed to the new rules. The remaining increase would come about as a result of previous energy policy.

"Consumers can retain choice, but for more fuel-efficient cars. Every single category of car will be more efficient," the official said, noting that fuel savings would offset much of the higher cost.

The announcement today marks a major change in tone from the Bush administration, which had rejected California's waiver in March 2008, and so barring states from setting their own limits on greenhouse-gas emissions from automobiles. Obama had ordered the EPA to reconsider the ruling.

Under the compromise, the U.S. government will establish two sets of standards: one for mileage, and one for tailpipe emissions of carbon dioxide.

The U.S. Transportation Department's National Highway Traffic Safety Administration will set the new fuel-economy standards. Cars, for instance, would need to average 39 m.p.g. by 2016 while light trucks would need to reach 30.

The Environmental Protection Agency, using its power to regulate carbon-dioxide emissions under a 2007 Supreme Court ruling, plans a tailpipe-emissions standard of 250 grams per mile for vehicles sold in 2016, roughly the equivalent of what would be emitted by vehicles meeting the mileage standard. Vehicles sold in 2009 are expected to emit about 380 grams per mile, industry sources said.

'To the table'

One person involved in the negotiations said the Supreme Court's ruling on regulating emissions helped push companies to bargain because they feared the prospect of having to comply with separate EPA standards in addition to those from California.

"That's what brought the companies to the table," the source said.

In addition, many of the automakers that originally fought California's standards are now struggling for survival and in a weaker position to fight. Their opposition also waned after last year's high gas prices and consumers' newfound frugality, which shifted the mix of vehicles being sold toward more fuel-efficient models.

General Motors said yesterday that in 2008, the average fuel efficiency of its cars was 29.7 miles a gallon, higher than the 27.5 requirement; its new trucks got 23.2 m.p.g., somewhat higher than the 22.6 m.p.g. requirement.

'Pleased'

In a statement, Ford Motor Co. said: "We are pleased that President Obama is taking decisive and positive action as we work together toward one national standard for vehicle fuel economy and greenhouse-gas emissions."

The EPA is also expected to impose restrictions on greenhouse-gas emissions resulting from leaks of air-conditioning coolant in vehicles. The automakers would be able to use some credits for complying with those regulations to offset a small part of fuel-efficiency requirements.

Proponents of tougher fuel-efficiency standards hailed reports of the announcement.

"If media reports are true, after years of oil price inflation, policy stagnation and automotive industry litigation, President Obama has solved the energy and economic policy equivalent of a Rubik's Cube," said Rep. Edward J. Markey (D., Mass.), a principal author of the 35 m.p.g. standard that Congress adopted in 2007.