Young activists who are suing the U.S. government in a high-profile climate change lawsuit say the case poses important constitutional questions that should be fully evaluated at trial next week.

The 21 young people issued a response Monday after the U.S. Supreme Court temporarily put the trial on hold. Lawyers for the young people, ages 11 to 22, argue that the move "will disrupt the integrity of the judiciary's role as a check on the political branches and will irreparably harm these children."

The trial had been set to start Oct. 29 in federal court in Eugene, Oregon. The lawsuit filed in 2015 argues that government officials have known for more than 50 years that carbon pollution from fossil fuels was causing climate change and that policies on oil and gas deprive the young people of life, liberty and property.

They also say the government has failed to protect natural resources as a "public trust" for future generations. The lawsuit wants a court to order the government to take action to quickly phase out carbon dioxide emissions to a certain level by 2100 and develop a national climate recovery plan.