U.S. President Barack Obama speaks during the National Christmas Tree Lighting and Pageant of Peace ceremony on the Ellipse near the White House in Washington December 3, 2015. REUTERS/Yuri Gripas

WASHINGTON (Reuters) - President Barack Obama defended his remarks about the threat posed by climate change, saying Republicans, including U.S. presidential candidate Donald Trump, were "the only people" disputing the gravity of the problem.

Obama has called climate change a great threat to future generations. At a news conference on Tuesday before leaving the U.N. climate summit in Paris, he likened global warming to the threat posed by terrorism and Islamic State and said both problems can be addressed by applying steady pressure and new ideas.

Republicans seized on his comments as understating the threat of terrorism. Trump, front-runner to be the Republican nominee in the 2016 presidential election, told MSNBC that Obama's comment was the "one of the dumbest statements I've ever heard in politics."

"Well, you know, Mr. Trump should run back a tape or quote on some of the stuff he's said," Obama retorted, during an interview with CBS "This Morning" that was broadcast on Friday.

"But, look, here's what we know: 99.5 percent of scientists in the world say this is a really urgent problem," he said. "Political parties around the world. The only people who are still disputing it are either some Republicans in Congress or - folks on the campaign trail.”

Obama was among more than 150 world leaders in Paris this week at the start of a U.N. conference that aims to reach an agreement to curb global warming.

On Tuesday, Obama said rising seas and warming climates could be drain on economic resources.

"This is an economic and security imperative that we have to tackle now," he said.

(Reporting by Doina Chiacu; Editing by Frances Kerry)