(CNN) White House national security adviser HR McMaster said Saturday that North Korea represents "the greatest immediate threat to the United States" and that the potential for war with the communist nation is growing each day.

"I think it's increasing every day, which means that we are in a race, really, we are in a race to be able to solve this problem," McMaster told an audience at the Reagan National Defense Forum in Simi Valley, California when asked if North Korea's launch of an intercontinental ballistic missile Tuesday had increased the chance of war.

President Donald Trump remains committed to the complete denuclearization of the Korean Peninsula, McMaster said, adding that there are nonmilitary ways to deal with the issue, such as calling on China to impose greater economic sanctions against Pyongyang. McMaster noted that Beijing's "tremendous coercive economic power" over North Korea.

"There are ways to address this problem short of armed conflict, but it is a race because he's getting closer and closer, and there's not much time left," McMaster said, referring to North Korean leader Kim Jong Un. With every missile launch or nuclear test, Kim has improved his country's capabilities, McMaster said.

"We're asking China not to do us or anybody else a favor," he said. "We're asking China to act in China's interest, as they should, and we believe increasingly that it's in China's urgent interest to do more."

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