There’s “no way to stop” Kim Jong Un’s regime and its missile and nuclear program, a North Korea expert told Fox News on Thursday, the warning coming amid Pyongyang’s continued threats to sink Japan and blast the U.S. “into ashes and darkness.”

Leading Seoul-based North Korea expert Andrei Lankov told Fox News that Kim Jong Un is accelerating his missile and nuclear program “much faster than anybody expected.”

“They want to get the point of having a sufficient number of intercontinental ballistic missiles capable of destroying a sufficient number of American cities,” Lankov said.

The expert expressed doubt about reining in North Korea’s trajectory in achieving its military goal, adding the use of any “military force” would send the peninsula into war. He said sanctions and regional diplomacy wouldn’t work, either.

“I don’t think, unfortunately, there is no way to stop them,” Lankov said. “No way…A use of military force, but that would result in a second Korean war. That would be an absolute disaster.”

He added: “They will not want to talk about denuclearization…they could talk about a nuclear freeze…in exchange for political and economic concessions.”

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