Transcript for Trump shakes hands with Kim at summit

Our white house team is reporting president trump is expected to watch at least some of Cohen's testimony even though it will be on in the middle of the night there. He's sitting down first though with -- for dinner with Kim Jong-un. Our chief white house correspondent Jonathan Karl is there in Hanoi with the very latest. Jon, the president now seems to be lowering expectations before this big summit. Reporter: He does, Cecilia, but just now we saw a full display of one of the world's strangest and most unlikely relationships here in Vietnam as the president had his second face-to-face meeting with Kim Jong-un. The second time in less than a year president trump and north Korean dictator Kim Jong-un greeted each other on the world stage with handshakes and smiles. It's an honor to be with chairman Kim. I thought the first summit was a great success and I think this one hopefully will be equal or greater than the first. Reporter: Even before today's opening handshake, president trump sounded an optimistic tone for summit part two. We have a very big dinner tonight as you know and meetings with North Korea and chairman Kim and we both felt very good about having this very important summit in Vietnam. Reporter: In a tweet earlier today president trump declared that the north Korean economy would be booming if it would denuclearize saying, quote, the potential is awesome. A great opportunity like almost none other in history for my friend, Kim Jong-un. As Kim seeks relief from crushing economic sanctions U.S. Intelligence officials say they see no sign North Korea is ready to give up its nukes. Amidst the fanfare surround the Nice to see you. Reporter: The world has caught a few unscripted glimpses of the reclusive north Korean dictator. Japanese TV see him puffing a cigarette during a break along his 65-hour train ride while his sister held an ashtray but the big question, can this second summit achieve concrete results? As for what those concrete steps could be, the United States would like to see North Korea allow inspectors to come in to look at its nuclear facilities and to begin a process of actually dismantling them. So far North Korea has not even provided an accounting for how many nuclear weapons it has and what exactly constitutes its nuclear program. What's most striking here, robin, is just how much is up in the air even as the two leaders are starting to meet. I spoke with a senior official with the president on this who said they don't know what to expect tomorrow. They won't know until they see how dinner goes tonight. So much still up in the air, Jon. As we all know this meeting

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