SAN FRANCISCO, May 9 (Xinhua) -- A coalition of 15 U.S. states is filing a new lawsuit challenging President Donald Trump's executive order declaring a "national energy emergency," which aims to accelerate fossil fuel development.

Washington State Attorney General Nick Brown announced the legal action Friday during a press briefing. The 61-page complaint was submitted to the U.S. District Court for the Western District of Washington.

According to the lawsuit, Trump's order violates the National Emergencies Act of 1976, which was designed to ensure that presidents use their emergency powers "only when actual emergencies exist" and not for "frivolous or partisan matters."

"Prodded onto the shakiest of limbs by the President's unsupported and unlawful Executive Order, multiple federal agencies now seek to broadly employ these emergency procedures in non-emergency situations," the lawsuit said.

Brown criticized Trump's emergency declaration as "fake," as U.S. energy production is at an all-time high level.

"This is not a serious or lawful effort by the president. It is all about eliminating competition and shackling America to dirty fossil fuels forever," Brown said at a news conference held in Seattle.

Trump issued the executive order on his first day back in office earlier this year. It promotes the expansion of oil, gas, coal, and other fossil fuel sources, while explicitly excluding wind, solar, and battery-based energy initiatives.

"Our Nation's current inadequate development of domestic energy resources leaves us vulnerable to hostile foreign actors and poses an imminent and growing threat to the United States' prosperity and national security," Trump declared in the executive order.

Federal agencies have since begun to bypass or reduce environmental review requirements under laws such as the Clean Water Act, the Endangered Species Act, and the National Historic Preservation Act, the lawsuit alleges.

The legal filing seeks a court ruling to invalidate the executive order and to prohibit federal agencies from issuing fast-tracked permits based on the order.

States joining the suit include California, Arizona, Connecticut, Illinois, Massachusetts, Maine, Maryland, Michigan, Minnesota, New Jersey, Oregon, Rhode Island, Vermont, and Wisconsin. ■