California sued the U.S. Environmental Protection Agency on Wednesday for denying its first-in-the-country greenhouse gas limits on cars, trucks and SUVs, challenging the Bush administration's conclusion that states have no business setting emission standards.

Other states are expected to join the lawsuit, which was anticipated after the EPA on Dec. 19 denied California's request for a waiver, required under the federal Clean Air Act. The lawsuit was filed in the 9th U.S. Circuit Court of Appeals in San Francisco. At least 16 other states had been expected to follow California's lead and adopt the state's tougher emission limits.

EPA Administrator Stephen Johnson denied California the waiver, saying national energy legislation would be more effective than a patchwork of state regulations.

``There's absolutely no justification for the administrator's action,'' Attorney General Jerry Brown told The Associated Press in an interview Wednesday. ``It's illegal. It's unconscionable and a gross dereliction of duty.''

In announcing his decision last month, Johnson said the federal government was moving forward with a national solution and dismissed California's arguments that it faced unique threats from climate change.

Johnson said energy legislation signed by President George W. Bush will raise fuel economy standards countrywide to an average of 35 miles per gallon (equivalent to eight litres per 100 kilometres) by 2020.

In an emailed statement, EPA spokesman Jonathan Shradar said the federal Energy Independence and Security Act ``is a more beneficial national approach to a national problem, which establishes an aggressive standard for all 50 states, as opposed to a lower standard in California and a patchwork of other states.''

California officials contend their 2004 law is tougher than the new national standard. It would have required the auto industry to cut emissions by one-third in new vehicles by 2016 or reach an average of 36.8 miles per gallon (7.6 litres per 100 kilometres.)

Twelve other states _ Connecticut, Maine, Maryland, Massachusetts, New Jersey, New Mexico, New York, Oregon, Pennsylvania, Rhode Island, Vermont and Washington _ have adopted the California emissions standards and the governors of Arizona, Colorado, Florida and Utah have said they plan to adopt them. The rules also are under consideration in Iowa.

``(EPA officials) are ignoring the will of millions of people who want their government to take action in the fight against global warming,'' Gov. Arnold Schwarzenegger said in a statement. ``That's why, at the very first legal opportunity, we're suing to reverse the U.S. EPA's wrong decision.''

Fifteen states plan to intervene on California's behalf, including 13 of those that have either adopted or are in the process of adopting the rules. Delaware and Illinois, which have not passed the standards, also are part of the lawsuit.

``Today, there is simply no environmental issue more compelling _ or extraordinary _ than the increasing threat of climate change,'' New York Attorney General Andrew Cuomo said in a statement. ``Greenhouse gas emission standards for cars are a logical and necessary step to effectively combat global warming.''

The EPA's decision was a victory for automakers, which had argued that they would have been forced to reduce their selection of vehicles and raise prices in the states that adopted California's standards.

It was the first time the EPA had fully denied California a waiver under the Clean Air Act since Congress gave the state the right to obtain such waivers in 1967.

During a news conference announcing the lawsuit, Brown said the EPA's decision appears to have been made after ``White House pressure, automobile influence or some other lobbying pressure.''

``We understand this is a long fight that may go to the Supreme Court,'' Brown said. ``We feel this is going to be a struggle.''