The suit was filed in 2015 by a group of young people who said the government violated their right to “a climate system capable of sustaining human life.”

The Justice Department asked the Supreme Court on Thursday to put a stop to a massive environmental lawsuit, just over a week before it is scheduled to go to trial.

The suit was filed in 2015 by a group of young people, ranging in age from 10 to 21, who said the federal government has failed to stop climate change by promoting the use of fossil fuels for more than 50 years. They claim that policy violated their constitutional right to “a climate system capable of sustaining human life.”

They seek sharp reductions in carbon dioxide emissions and a national plan for restoring the earth’s energy balance. Despite repeated efforts by the federal government — under both the Obama and Trump administrations — to get the lawsuit tossed out, lower courts have allowed it to go forward.