Transcript for President Trump expected to ask Chinese president to take action against North Korea

president trump's warning that if schi that doesn't fix the problem, the U.S. Will step in and deal with North Korea ourselves. ABC's Bob woodruff tonight and his rare visit inside north Korea. You are able to see where they take them when Bob asks to S the bomb sites. Reporter: Tonight, a rare journey inside North Korea just as tensions with the U.S. Are escalating. While we're on the ground, president trump delivers a new message, telling "The financial times" the U.S. Is prepared to act alone to curb North Korea's nuclear ambitions saying quote, "If China is not going to solve North Korea, we will." These comments come after the north Koreans have made a show of testing several ballistic missiles during the beginning of the trump administration. We put in all sorts of requests to visit out here. The launch locations where the missiles are being launched. But instead, the north Koreans take us deep into the country, to see another prized achievement, the country's high end ski resort. Is there anyone else here? Are we the only ones? It's eerily empty. The few people on they slopes skiing to patriotic music coming from oversized screens. Meanwhile, several hundred miles away the us and south Korean troops continue to conduct joint military exercises. The top north Korean official for U.S. Affairs tells me, "Our army is at the highest alert." Rob, you reported that the U.S. Is willing to bypass China and take on North Korea directly if China doesn't solve the problem. What did you hear from north Koreans on this front? North Korea made it very, very clear. They demanded they speak only with the ugs, and not other countries. On the other hand, China wants the countries involved. North cee yarks I think that don't Vant to negotiate with the trump administration. Bob woodruff, thanks to you tonight. We are also on the scene of

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