(Bloomberg) -- Young climate activists who sued the U.S. in 2015 to force changes in government policy said the Trump administration’s actions increase the urgency for the case to go to trial.

“Another six months have passed without decision,” the youths said in a filing in the San Francisco federal appeals court this weekend, “while defendants continue to act in ways that further endanger plaintiffs’ lives, liberties, and property, as supported by additional, new evidence.”

The administrations of both Barack Obama and Donald Trump have repeatedly sought to kill the case, arguing the courts lack the authority to direct the executive branch to develop a comprehensive plan to cut greenhouse gas-emissions across the U.S. economy. A trial might take as long as four months, which would help keep attention on climate change through the 2020 elections.

The court put the case on a fast-track schedule in January and a three-judge panel signaled at a hearing in June that it agrees the government hasn’t done enough to address climate change. But the judges voiced uncertainty about whether courts can force broad action.

Read More: Kids’ Climate Claims ‘Compelling’ But Court Queries Own Role

The plaintiffs, who include University of Oregon student Kelsey Juliana, argue that the U.S. has violated a constitutional right to a livable climate over the last five decades.

In the latest filing, they submitted government documents that they say show a record expansion in recent years of oil and gas exploration and production on federal lands, as well as a marked increase in coal extraction.

Climate activism got a boost this year from Swedish teenager Greta Thunberg, who inspired millions of students to speak out on the issue, scolded world leaders at the United Nations General Assembly and mocked taunts by Trump and Brazilian President Jair Bolsonaro.

The Justice Department didn’t immediately respond to a request for comment.

The case is Juliana v. United States, 18-36082, U.S. Ninth Circuit Court of Appeals (San Francisco). The lower-court case is Juliana v. U.S.A., 15-cv-01517, U.S. District Court, District of Oregon (Eugene).

To contact the reporter on this story: Peter Blumberg in San Francisco at pblumberg1@bloomberg.net

To contact the editors responsible for this story: David Glovin at dglovin@bloomberg.net, Tony Czuczka, James Ludden

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