Republican presidential candidate Sen. Ted Cruz, R-Texas, campaigns Tuesday, Dec. 22, 2015, in Knoxville, Tenn. (AP Photo/Wade Payne)

KNOXVILLE, Tenn. -- Sen. Ted Cruz, who has questioned the existence of global warming, said Tuesday that if he were elected president, he would withdraw the United States from the landmark climate agreement reached in Paris earlier this month.

"Barack Obama seems to think the SUV parked in your driveway is a bigger threat to national security than radical Islamic terrorists who want to kill us. That’s just nutty," Cruz told reporters in a high school classroom here. "These are ideologues, they don’t focus on the facts, they won’t address the facts, and what they’re interested [in] instead is more and more government power."

Cruz has long sounded a skeptical note on climate change. He chairs the Senate subcommittee that oversees NASA and has said that the space agency needs to focus more on getting off Earth and less time studying what happens on the planet, specifically when it comes to matters of climate change.

The Texas Republican said at a Senate hearing earlier this month that temperatures on the Earth haven't changed in 18 years, sparring with a retired Navy rear admiral and meteorologist who said that the Earth's temperature had risen during that time.

"Those facts are, to use Al Gore’s phrase, an inconvenient truth," Cruz said in Knoxville. He accused the administration and other countries of using climate change as an excuse to increase regulations and make life more expensive.

"So they set them aside and continue to propose jacking up the cost of millions of Americans’ day to day living. Jacking up your car bill, jacking up your electric bill, jacking up the cost of people who are struggling," Cruz said.

Delegates from 196 nations approved a historic climate deal after 13 days of negotiating on Saturday, Dec. 12. Here's what you need to know about the accord. (Monica Akhtar/The Washington Post)

Earlier this month negotiators in Paris approved a historic climate accord that aims at limiting carbon dioxide emissions. It is not, however, binding, and the United States can walk away from it.

"In the event of a Republican administration that wants to undo the Clean Power Plan and other domestic regulations and to void the Paris agreement," Michael Burger, executive director of the Sabin Center for Climate Change Law at Columbia University and a lecturer at the school, told The Washington Post's Philip Bump earlier this month. "the option would be available to simply withdraw from the agreement."

This post has been updated.