Transcript for Trump warns North Korea threats 'will be met with fire and fury'

Tuesday night and we begin with North Korea. President trump warning the regime today against making any more threats toward the U.S. With that promise that the U.S. Would unleash fire and fury, the likes of which the world has never seen. It comes after U.S. Intelligence determined North Korea's weapons program has now reached a dangerous milestone. ABC's chief global affairs correspondent, Martha Raddatz, with president trump's entire statement on camera. His warning to North Korea. Reporter: It is the most fiery, overtly military threat president trump has ever launched at North Korea, a chilling warning in response Kim Jong-un's threats to the U.S. North Korea best not make any more threats to the united States. They will be met with fire and fury like the world has never seen. He has been very threatening, beyond a Normal standard, and as I said, they will be met with fire, fury and, frankly, power. The likes of which this world has never seen. Reporter: This dramatic escalation of rhetoric, all the more alarming given the latest extraordinary intelligence assessments of North Korea's nuclear capabilities. First reported in "The Washington post," and confirmed by ABC news, U.S. Intelligence analysts believe the north can now produce a miniaturized nuclear warhead that can fit inside its missiles including its intercontinental missiles. Kim Jong-un's claim that he was standing next to such a nuclear device last March was met with some skepticism, but this latest intelligence assessment says he has indeed produced that device. This is the most moment us day in his nuclear program. Reporter: Just two weeks ago, Kim tested an icbm into space, and farther than ever before. But analysts say if the missile trajectory was lowered, the missile could potentially reach the east coast of the united States including New York and Washington, D.C. There are still two pieces of the puzzle left. He has to show he has that nuclear warhead survive the heat of re-entry, and the second he has to be able to accurately target. Reporter: It is without question the greatest challenge president trump now faces. And the president's tough new words -- Fire, fury and frankly, power. Reporter: -- Come as Americans are worried about the north Korean threat according to polls. Just days after the un enacted strong sanctions, a CBS news poll found 61% of Americans are uneasy about president trump's handling of North Korea. And Martha Raddatz joins us from Washington tonight, and Martha, in addition to that miniature nuclear warhead, there were other alarming findings in that intelligence report? Reporter: There certainly were, David. U.S. Intelligence now believes North Korea has 60 nuclear weapons, a far greater number than they thought before, David. Martha Raddatz leading us off tonight. Thank you. I want to bring in Stephen ganyard, and you heard that U.S. Sbelgs believes the north Koreans developed a nuclear warhead that can fit inside that missile. That was the concern, was it not? What's the defense? It was, David. Because miniaturizing the weapon was the hard part of the capability. Look at this. This is what's called a ground base interceptor. If radars are able to detect a north Korean launch, missiles would be launched from Alaska and California, fly up into outer space. They would be able to tell the difference between a decoy warhead and the warhead itself, they would intercept itself like a bullet on bullet, and prevent that warhead from hitting the United States. That is the hope of how it would play out. Let me ask you this too. The president's words promising fire and fury like the world has never seen. Kellyanne Conway saying the president's rhetoric speaks for itself, calling it strong and obvious. What did you think as you heard it? David, this has been the de facto policy of the united States since president eisenhow Eisenhower, but the hear this language out of a U.S. President, it's something we have never heard before, and it puts the world on notice.

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