President Trump is doubling down on his tough talk on North Korea, telling Fox Business host Maria Bartiromo on Tuesday that dictator Kim Jong Un is “making a big mistake” with his nuclear provocations.

“I don’t know him,” Trump said. “But he’s doing the wrong thing.”

Late last week, the president deployed a U.S. Navy strike group to the vicinity of the Korean Peninsula. In turn, North Korea warned of tough counteraction against the U.S. if there is any sign of an American strike.

“We are sending an armada, very powerful,” Trump said. “We have submarines, very powerful, far more powerful than the aircraft carrier, that I can tell you.”

“We have the best military people on earth,” the president continued. “And I will say this. He is doing the wrong thing. He is doing the wrong thing.”

Related: Trump declares that North Korea is ‘looking for trouble’

Trump, though, declined to say what the United States is doing in terms of North Korea.

“You never know, do you? You never know,” he said. “You know I don’t talk about the military. I’m not like Obama.”

North Korea is one of Trump’s most difficult national security challenges. During the last two administrations, Pyongyang made enough progress on nuclear weapons and ballistic missiles that, experts predict, it could strike the U.S. mainland, possibly even the East Coast, in two to three years.

As Yahoo News previously reported, the Obama administration enlisted China and other world powers in two rounds of international sanctions and left Trump options for further tightening the economic vise, according to administration and congressional sources.

The aircraft carrier USS Carl Vinson, one of the vessels deployed to the Korean Peninsula. (Handout via Reuters)

Trump said he discussed the situation in North Korea with Chinese President Xi Jinping at his Mar-a-Lago estate in Palm Beach, Fla., last weekend.

“The first thing I brought up was North Korea,” Trump told Bartiromo. “I said, ‘You’ve got to help us with North Korea, because we can’t allow it. And it’s not good for you. And you have a tremendous power because of trade.’

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“I said, ‘Look, you have a tremendous power because of trading through the border,'” he continued. “If they don’t get food, they don’t get, you know, they can’t sell their coal. In fact, I hear today two massive coal ships from North Korea were sent back to North Korea, heading to China. They were sent back, which is a very good sign.”

On Tuesday, Reuters reported that China had ordered its trading companies to return coal shipments, a key North Korea export, to the Stalinist regime in Pyongyang.

Trump’s comments on North Korea came after a pair of tweets in which the president seemed to suggest that he would sweeten the terms of a trade agreement with China if Beijing assists in solving the North Korean “problem” — but that the U.S. is prepared to move forward in the western Pacific without Chinese help.

I explained to the President of China that a trade deal with the U.S. will be far better for them if they solve the North Korean problem! — Donald J. Trump (@realDonaldTrump) April 11, 2017





North Korea is looking for trouble. If China decides to help, that would be great. If not, we will solve the problem without them! U.S.A. — Donald J. Trump (@realDonaldTrump) April 11, 2017





“I explained to the President of China that a trade deal with the U.S. will be far better for them if they solve the North Korean problem!” Trump tweeted Tuesday morning.

“North Korea is looking for trouble,” Trump continued. “If China decides to help, that would be great. If not, we will solve the problem without them! U.S.A.”

“I think China can help us,” he told Bartiromo. “I hope China can help us. We talked about trade, and I can tell you, China will do much better on trade if they help us with North Korea.”

Yahoo News Chief Washington Correspondent Olivier Knox contributed to this report.

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