Transcript for Trump administration expresses concern about North Korea's nuclear threat to the US

either with Republicans or DEMs. Tom? The nuclear am decisions are a growing threat to the united States. North Korea could hit the U.S. Are with missile before the end of president trump's turn. Bob woodruff in North Korea tonight. Reporter: We arrive in the reclusive country at this time of rising tensions with the U.S. Our hosts make a point to show us the growing capital city of Pyongyang. But we hope to see something else, those sites where the north Koreans have launched missiles and a new rocket engine since president trump took office. We put in all sorts of requests to visit out here the launch locations where the missiles are being launched. We asked if we could see those brand new rocket engines. We're not getting that, but they said they were gonna take us skiing. On the road deep into the countryside, we drive by soldiers walking in formation. Then arrive as promised at north Korea's brand new ski mountain, with all the trappings of a resort -- Are there any other guests here? Or the only ones? Reporter: Except, it's eerily empty. The few people on the slopes skiing to patriotic music. Back in the capital, the top north Korean official for U.S. Affairs grants us a rare interview, and we talk about secretary of state Rex tillerson's recent tough talk. Let me be very clear, the policy of strategic patience has ended. All options are on the table. Reporter: Vice foreign minister Han song-ryol says he thinks the possibility of a pre-emptive strike against the country's nuclear program is strong. Later adding, if you bring out a knife to attack us, we will take out a sword. Mr. Han told me he has never met, personally, president trump before but he's read that he's a great businessman, and he heard that he's very unpredictable, which means that he is preparing for everything, Tom. Bob woodruff reporting from

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