Environmentalists are gunning for the Environmental Protection Agency in a new lawsuit that says the agency is "foot dragging" on issuing new regulations to cut greenhouse gas emissions from aircraft, potentially jeopardizing President Obama's leadership position in the global fight against climate change.

"Airplanes' skyrocketing climate pollution requires urgent action, not more foot dragging from the Obama administration," said Vera Pardee, senior attorney with the Center for Biological Diversity's Climate Law Institute, in a statement after filing the challenge in federal appeals court. "The EPA has dawdled for almost a decade, even as airplane emissions are on track to spiral out of control."

"We can't afford more denial and delay in tackling this high-flying threat to our climate," Pardee said.

The legal group Earthjustice filed the lawsuit Tuesday in the D.C. Circuit Court of Appeals on behalf of the center and the environmental group Friends of the Earth.

The groups say regulating aircraft emissions is part of the administration's climate change agenda, referenced in the president's plan to meet the nation's obligations under the climate deal he agreed to last year in Paris. But the groups say those commitments mean next to nothing in terms of real emission cuts.

"President Obama will show his commitment to fighting climate change when he signs the Paris Climate Agreement, but the standards he is prepared to accept for carbon pollution from airplanes are embarrassingly low," said Sarah Burt, a legal expert on aircraft pollution with Earthjustice. "There is an opportunity for Obama to continue his global leadership on climate change by advancing stronger protections. As the largest contributor to aircraft carbon pollution, the U.S. should lead the way to meaningful action on this source of emissions."

Obama is expected to sign the Paris accord next week when signing of the agreement opens on Earth Day, April 22, at United Nations headquarters in New York.

The lawsuit is part of a long effort by environmental groups to hold the EPA to account on emissions. The center, along with Friends of the Earth and other environmental organizations represented by Earthjustice, sued the agency in 2010 to force it to set standards for aircraft. They won their suit, with a judge ruling that EPA is required under the law to address aircraft emissions.

In 2015, under renewed legal pressure, the EPA proposed what is known as an "endangerment finding," showing that carbon emissions from aircraft pose a threat to the global climate. It is the first step to proposing regulations.

"But the proposed 'endangerment finding' does not make a final determination, and EPA did not propose emission standards," the groups say. They say the agency recently announced that 2017 would be the earliest date for publication of a proposed rule, with 2018 as the earliest possible date for regulations to become law.