Transcript for Trump blasts Michael Cohen after guilty plea

Vega. Great to be here. What a huge news day you had yesterday. A big news day, a big bombshell. Repercussions for the president and what we'll get to. He meets with world leaders in Argentina today. This comes on the heels of that Russia investigation bombshell placing trump at the center of an effort to build a tower in Moscow during his presidential campaign. The president's former lawyer, Michael Cohen, now admitting he lied to congress about it to protect his boss and Jon Karl in buenos aires with the president. Good morning, Jon. Reporter: Good morning. With a whirlwind two days of meetings, just getting under way now in Argentina, there is a new reality weighing on the trump presidency, the president's longtime confidant, Michael Cohen, has spent 70 hours in interviews with special counsel Robert Mueller. As the president takes the world stage this morning here in Argentina, signing a new trade deal with Canada and Mexico and high-stakes meeting to prevent a trade war with China he is facing mount troubles back home. President trump's longtime fixer has now gone state's witness. Michael Cohen entering a plea agreement with special counsel Robert Mueller. It's a move wit massive implications for the special counsel investigation and perhaps the trump presidency. Cohen has admitted to lying to congress about working during the 2016 campaign to strike a deal to build a trump tower in Moscow. And he says he was lying to protect his longtime boss, Donald Trump. As the president left the white house for Argentina, he lashed out at his former fixer. He's a weak person and not a very smart person. Very simply, Michael Cohen is lying and he's trying to get a reduced sentence for things that have nothing to do with me. Reporter: The president did not deny trying to pull together the Moscow deal even as he was campaigning for president. When I run for president, that doesn't mean I'm not allowed to do business. I was doing a lot of different things. After I won obviously I don't do business. Reporter: For more than two years he insisted he had no business ties with Russia. But zero. I will tell you right now, zero. I have nothing to do with Russia. Reporter: Throughout his campaign and into his presidency president trump has talked about the need for the U.S. Government to have closer ties with Russia. Wouldn't it be great if we got along with Russia? Wouldn't it be great? Is there anything wrong with that? Reporter: He said he ditched the Moscow project in early 2016 before he clinched the Republican nomination but he says he didn't have to. There would be nothing wrong if I did do. I was running my business while I was campaigning. There was a good chance that I wouldn't have won in which case I would have gotten back into the business and why should I lose lots of opportunities? Reporter: And while the president was on air force one flying down here to Argentina, another surprise. He abruptly canceled his planned meeting with Vladimir Putin. He was going to meet with him right here, very highly anticipated meeting and the president said he was calling it off because of Russian aggression in Ukraine. Okay, Jon Karl, thanks very much. Let's bring in Dan Abrams. We saw the president say this had nothing to do with him. One reason it's so important, it does put the president right at the center of this effort. Right, and the question becomes, why, right? We talked about this before, this is a piece in the puzzle. This isn't the smoking gun but the question becomes, why did the president, if Cohen is telling the truth, want to move the date back from June to January? Why is that six-month period so important? And the answer would be if it's true that he didn't want to be seen as talking to Russia during the period right when you've got all the hacking, the meeting with don junior, this is the heart of the contacts and the problems with the Russians is happening in June. He gets another important thing that Mueller and reporters have uncovered now over the last year and a half. When it comes to Russia, whether it is contacts or building the trump tower in Moscow or the attorney general talking to a Russian ambassador during the campaign, don junior having this meeting, every single time it starts out with a lie then the lie is uncovered. Mueller's job is to find out why. Also his job is to put them all together. You can't look at each one in isolation and say, Flynn, what is Flynn's single lie tell us? That's not the question. The question is what does Flynn's lie tell us in connection with the other lies. Why is everyone seemingly distancing themselves from either conversations they had, meetings, et cetera, with Russians? What was going on? The big picture. We know Michael Cohen has implicated the president on campaign finance felonies and implicated the president in trump tower and as Jon said we reported yesterday, he spent 70 hours with Mueller's team. This is not over. Right, and so knowing how close Michael Cohen was to Donald Trump, you know Donald Trump has to be worked. I mean, regardless of what we already know already, the idea that one of his closest confidants, and, remember, attorney/client privilege only applies to legal work, not business work so he can talk about any business contacts that the president had and that's got to be unnerving. Dan Abrams, thanks very much.

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