Transcript for President Trump meets with world leaders at G7 summit

We want to move to politics. President trump is leaving the g7 early. This morning after a whirlwind day of meetings with U.S. Allies. The president's storied criticism over his comments on trade and suggesting Russia should be allowed back into the group. ABC's David Wright is in Quebec city with the details. David, good morning. Reporter: Good morning, whit and Paula. This g7 summit has been fraught from the start with president trump arriving here late after stopping to take some pot shots at the other world leaders from the white house lawn, and today trump is bugging out early. Right from the start here in Quebec the U.S. President has been odd man out. The tension palpable. After trump's threat to impose stiff new tariffs on some of America's closest allies. The European union treats us very unfairly. Canada, veryunfairly, Mexico, very unfairly. Reporter: His host, Canadian prime minister Justin Trudeau fumes that trump seeks to justify the new tariffs on national security grounds. The idea that we are somehow a national security threat to the United States is quite frankly insulting and unacceptable. Reporter: So trump tried to smooth things over with humor. Justin has agreed to cut all tariffs and all trade barriers between Canada and the united States, so I'm very happy about that. Nafta is in good shape. But we are actually working on it. Reporter: Trump also had kind words for French president Emmanuel macron. He's my friend. We had a great relationship right from the beginning. Reporter: But he acknowledged the differences too. We have a little test every once in a while when it comes to trade. The United States has had a tremendous big trade deficit many years with the European union. Reporter: As if these trade issues weren't thorny enough, trump also ruffled feathers by calling on the world's club of leading industrial nations to give Russia a seat at the table. Russia should be in this meeting. Why are we having a meeting without Russia being in the meeting? Reporter: Russia was expelled from this group after it illegally annexed crimea and the other world leaders have no intention of reconsidering that. Sometimes we disagree, but we always speak and share I think common concerns and common values. Reporter: The French president philosophical there but elsewhere he's been a bit more pointed. Earlier this week macron tweeted in English no less, the American president may not mind being isolated but neither do we mind signing a six-country agreement if need be. Whit and Paula, they call this the g7 but here in Quebec the phrase we keep hearing this year is it's the g6 plus 1. Thanks so much. We appreciate it. President trump, meantime, leaving the summit early to head to Singapore where he will have that historic face-to-face meeting with Kim Jong-un. The world waits to see what's going to happen and ABC's white house correspondent Tara Palmeri is in Singapore for us with the preview of the very high stakes talks. Tara, good morning. Reporter: Good morning, Paula and whit. This is the ultimate deal for president trump who has already floated the idea of a Nobel peace prize if he's able to get Kim Jong-un to give up his nukes. At the same time he's tempering expectations saying he'll be fine with going home with just normalized relations with north Korea and a follow-up summit in the U.S. On Friday, president trump said he'll be cramming on the flight to Singapore for that historic summit with Kim Jong-un. I have work. I have about 15 boxes of work. Reporter: This missing report says he's been lax ahead of the high-stakes meeting with the north Korean leader. I've been preparing all my life. Reporter: Just a day earlier saying it's all about personal chemistry. I don't think I have to prepare very much. It's about attitude, it's about willingness to get things done. Reporter: All this as president trump attempts to do what no other president has done before, sit face-to-face with a north Korean leader and make the case for total and irreversible denuclearization. There's a potential for change here, but because north Korea has lied and cheated at every turn for the past 60 years, the U.S. Negotiators are going to be on guard. Reporter: The president downplaying expectations. I believe we're going to have a terrific success or a modified success. Reporter: At the same time, ready to play hardball. I am totally prepared to walk away. I did it once before. Reporter: In Singapore the city gearing up for the big event. There's a strong police presence and construction crews are laying down barricades. This is sentosa, a man-made island off the coast of the main island of Singapore, and behind me is the hotel where president trump will meet with Kim Jong-un for the first time. Now, as you can see from the tents over there, security is ramping up, even though the event is still three days away. Meanwhile, former NBA player and "Celebrity apprentice" contestant, Dennis rodman. Dennis rodman. Reporter: Said he'll also be flying to Singapore for the event. He's one of the few Americans who has met both Kim and trump. President trump said rodman may be in town but he won't be welcome at the summit. Kim Jong-un's advance team has descended on the St. Regis hotel where he's staying. There are tons of road closures in that area. Earlier the U.S. Air force conducted drills in the skies of Singapore. Paula, whit. I can imagine the entire city is going to be on lockdown. A lot of planning. Yep. Lots of planning. Tara, thank you.

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