Transcript for World reacts to historic North Korea, US summit

Also moments ago president trump arriving back in Washington, D.C., of course, after that historic summit in Singapore. But there are still a lot of questions this morning about what was actually agreed to and what comes next. George leading our coverage from Singapore and, George, the president just tweeting about this. He sure did. He was definitive, Amy. He said there is no longer a nuclear threat from North Korea but as you said there are lots of questions. The president's summit with Kim Jong-un has really delivered a shock to the entire global system. It's being felt in capitals all across this region, being felt in China and South Korea. We're also getting the first reaction from North Korea. Got to show you this here, the official north Korean newspaper, 34 pictures of the trump/kim summit. Lots of talk about the president's concessions saying the president has agreed to stop those military actions, also saying something the white house has not said publicly, that the president committed also to ending sanctions, to lifting sanctions on North Korea but check had out. In a six-page spread, the word denuclearization appears just once, it's that one tiny word highlighted in yellow right there and it doesn't even say that it's North Korea that's committed to denuclearize but say it is an obligation on both sides. There are, as you say, lots and lots of questions right now, want to bring in our chief white house correspondent Jon Karl. Lots of questions on capitol hill as well but the president is being definitive. The president absolutely is being definitive on this despite those questions. Take a look at another tweet. Before taking office people were assuming that we were going to war with North Korea. President Obama said that north Korea was our biggest and most dangerous problem. No longer, sleep well tonight. So despite those questions being asked by some members of his own party the president clearly believes he has scored a master stroke here that could define his presidency. On the long flight home from Singapore, the president offered a big thank you to his new negotiating partner. The world has taken a big step back from potential nuclear catastrophe, he tweeted. No more rocket launches, nuclear testing or research. The hostages are back home with their families. Thank you to chairman Kim, our day together was historic. Overnight north Korean state media lauded the deal saying it has put an end to the extreme hostile relations between north Korea and the U.S. Okay. Reporter: At home the reaction has been mixed. With some of the president's foal LE Republicans openly wondering if he gave up too much for too little. I read the statement and it's difficult for me to see if something was actually agreed to or not. Reporter: One concession that is raising concerns what the president told George about putting an end to the joint U.S. South Korean military exercises. We're not going to play the war games. You know, I wanted to stop the war games. I thought they were very provocative but also think they're very expensive. Reporter: Ending the war games has been a north Korean demand and in the past the U.S. Has said they're essential for military readiness. I'm doing something I've wanted to do from the beginning, we stopped playing those war games that cost us a fortune. We're spending a fortune every number of months doing war games with South Korea and I said, what's this costing? Reporter: The Pentagon said defense secretary Mattis was consulted on the offer but the move caught South Korea by surprise. In the joint agreement president trump promised unspecified security guarantees for Kim and Kim declared his, quote, unwavering commitment to denuclearization of the Korean peninsula. The details and whether it will be verified still to be worked out. You trust him? I do trust him. Now, will I come back in a year and you'll interview and I said, gee, I made a mistake, it's always possible. Dealing at a high level. A lot of things can change. A lot of things are possible. He trusts me. Reporter: There is no mention of human rights although the president has called North Korea the most brutally repressive regime on Earth. Do you still believe that is the case having sat down with Kim Jong-un and does he need to change that? Jon, I believe it's a rough situation over there. There's no question about it and we did discuss it today pretty strongly. A new story, a new beginning. Reporter: There are new details about the slickly produced video that president trump says he showed Kim during the summit. The white house says it was created by the national security council to help the president demonstrate the benefits of complete denuclearization and a vision of a peaceful and prosperous Korean peninsula. And about the president's praise for Kim Jong-un, his personal praise for the dictator, he's getting pushback on that. Marco Rubio, the Republican senator from Florida says Kim Jong-un is not a talented guy. He inherited his family business from his dad and grandfather. He is a total weirdo. Now, Rubio also says that the president was simply trying to butter him up to get a better deal but all of this lavish praise on Kim Jong-un is something that is not sitting well with a lot of Republicans. Everyone trying to figure out what it means so let's bring in

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