WASHINGTON - The Environmental Protection Agency tonight slapped down California's bid for first-in-the-nation greenhouse gas limits on cars, trucks and SUVs, denying a request for a waiver that would have allowed those restrictions to take effect.

At least a dozen other states, including Pennsylvania and New Jersey, have adopted the same standards. They, too, will be unable to implement them.

In explaining the decision, EPA Administrator Stephen L. Johnson cited energy legislation - approved by Congress and signed today by President Bush - that includes the first increase in federal fuel efficiency standards in 32 years.

"The Bush administration is moving forward with a clear national solution - not a confusing patchwork of state rules," Johnson told reporters. "I believe this is a better approach than if individual states were to act alone."

The long-awaited decision amounted to a serious setback for states seeking the new car regulations to achieve their anti-global warming goals.

The tailpipe standards that California adopted in 2004 would have forced automakers to cut greenhouse gas emissions by 30 percent in new cars and light trucks by 2016, with the cutbacks beginning in the 2009 model year.

Under the Clean Air Act, the state needed a federal waiver to implement the rules.

"It is disappointing that the federal government is standing in our way and ignoring the will of tens of millions of people across the nation. We will continue to fight this battle," said Gov. Arnold Schwarzenegger. "California sued to compel the agency to act on our waiver, and now we will sue to overturn today's decision and allow Californians to protect our environment."

In addition to Pennsylvania and New Jersey, the standards have been adopted by Connecticut, Maine, Maryland, Massachusetts, New Mexico, New York, Oregon, Rhode Island, Vermont and Washington. And the governors of Arizona, Colorado, Florida and Utah have said they also planned to adopt them.

The federal energy legislation signed today requires automakers to achieve an industrywide average fuel efficiency for cars, SUVs and small trucks of 35 miles per gallon by 2020.

California's law is worded differently - requiring passenger cars and some small sport utility vehicles and trucks to reach 43.7 miles per gallon by 2016. Most pickups, SUVs and larger vehicles would need to achieve 26.9 m.p.g. by 2016.

Johnson, the EPA administrator, said Congress' approach of reaching a fleetwide average of 35 m.p.g. would be better than a "partial state-by-state approach" that would achieve 33.8 m.p.g.

But environmental groups questioned that reasoning, noting that California's standards would be higher a full four years earlier, and the federal 35 m.p.g. was a minimum requirement that future administrations could exceed.

"This is fundamentally misleading," said David Doniger, director of the climate center for the Natural Resources Defense Council.

A decision had been awaited for two years but EPA put it off while the Supreme Court considered whether it could regulate greenhouse gases.

In April, the Supreme Court said it could.

Associated Press writer Samantha Young in Sacramento contributed to this report.