Transcript for EXCLUSIVE: Trump cites Nixon, says he 'was never going to fire Mueller'
Only a small portion of George's extensive interview with the president has aired so far and those excerpts are reverberating throughout Washington. In just a moment, you'll see new scenes from our all-access ABC news exclusive. George asked the president questions that Robert Mueller never had a chance to ask him. But first, to underscore the significance of what we have already heard from the president, he did not see a problem accepting help from a foreign country, an adversary, even, to win a second term. And if he received that kind of offer, he may or may not tell the FBI about it. That comment surprised some of the president's closest allies. But it was also classic Donald Trump, bluntly saying exactly what was on his mind without regard for the political repercussions. Prominent Republicans have stepped forward to disagree with the president on this. A and senate Democrats tried to pass a bill that would make it a crime to fail to report interference in an election. The president has since sought to clarify his comments. He called into "Fox and friends" saying he would review the material from a foreign entity and report it if it was, quote, something bad. Then this weekend, he tweeted that he enjoyed his interview with George. Also this morning, another big ABC news exclusive. We will be joined live by Progressive fire brand Alexandria ocasio-cortez. She's part of the growing chorus in the house calling for an impeachment inquiry. She may also be the sought-after endorsement in the democratic presidential primary. But now, more from George's interview with the president. Reporter: Over two days, president trump and I covered a lot of ground. Look who's in the back of the car. Him, right here. Reporter: Starting in Iowa on Tuesday, where we rode together in his brand-new armored limo, the beast. This some piece of machinery. This is amazing, actually. Reporter: The conversation turned tense when the president raised Mueller himself. What's your pitch to the swing voter on the fence? Safety, security, great economy. I think I've done more than any other first-term president ever. I have a phony witch-hunt. Which is just a phony pile of stuff. Mueller comes out, there's no collusion and no obstruction. They keep going with it. You know what, people are angry about it. I don't think that's what he found. We don't have time for that. That's what he found. Excuse me, he found no collusion and he didn't find anything having to do with obstruction. They made a ruling based on his findings. They didn't investigate collusion. He said no collusion. He said he didn't look at collusion. The report said, no collusion. Did you read the report? Yes, I did. You should read it, too. Reporter: Back at the white house on Wednesday, we were invited to the oval office where the president returned to the Mueller report unprompted. This time, responding to a question about polling of 2020 that he doesn't like. Why does it bother you so much? It's untrue. I like the truth. You know, I'm a very honest guy. If I thought they were correct, I wouldn't be complaining at all, I understand that. It's like, the witch-hunt that goes on. No collusion with Russia. There was no collusion. And what bothers me -- As you know, that's not what Robert Mueller found. No collusion. Reporter: In fact, the report cites 126 contacts between the trump campaign and Russia. George, all I want is the truth. All I want is fairness. But you say that, for example, you're pursuing a trump tower in Moscow during the campaign and denying any relationship with Russia. George, let me tell you, I didn't even do a deal in Moscow. Excuse me, excuse me. Pursuing, what is pursuing? You know I don't think they had a site. It was a concept of a deal. More of a concept than anything else. It was a concept of a deal someplace in Russia, probably Moscow. Didn't voters have the right to know that. I wouldn't mind telling them. There's nothing wrong. I didn't consider that pursuing a deal when you don't even have a site. Reporter: Then, that stunning admission about the prospect of accepting help from a foreign power in 2020. This campaign under, if foreigners, if someone else offers you information on an opponent, call the FBI? I think maybe you do both. I think you can listen. There's nothing wrong with listening. If somebody called from a country, Norway, we have information on your opponent. Oh. I think I'd want to hear that. You want that kind of interference in our elections? It's not an interference. They have information. I think I'd take it. I'd go to the FBI if there was something wrong. When someone comes one oppo-research, let's call the FBI. The FBI doesn't have enough agents to take care of it. But you talk honestly to congressmen they all do it. It's called oppo-research. Reporter: Later that day, I asked him about Mueller's findings on obstruction of justice. In a statement signed by more than 1,000 former prosecutors who believe trump was spared from indict M only because of a justice department opinion because a sitting president can't face criminal charges. The attorney general said you didn't commit obstruction of justice. Robert Mueller said he could not exonerate you and he laid out all that evidence. More than 1,000 former prosecutors -- Hey, George, look, I know more about prosecutors than you'll ever know. They're politicians. I could get 5,000 that would also say that there's nothing. I saw the names and these are -- many of them are trump haters. Many of them. Many Republicans -- I can give you thousands. We could get you thousands of prosecutors. I've been treated so unfairly because I never did anything. There was no crime. One of those prosecutors kamala Harris -- She's running president. She's doing horribly. She's way down in the polls. Pocahontas is really cleaning her clock. I heard she made that statement. Who wouldn't? Probably if I were running many her position, I'd make the same statement. Reporter: I asked about possible obstruction of justice. You ask your counsel don mcgahn said, Mueller has to go. You call him twice, Mueller has to go, call me when I's done. The story on that very simply, number one, I was never going to fire Mueller. I don't care what he says. It doesn't matter. That was to show everyone what a good counsel he was. Now, he may have gotten it confused with the fact that I have always said, I said to you and anybody who would listen, Robert Mueller was conflicted. But why would don lie under oath -- Because he wanted to make himself look like a good lawyer or, or he believed it because I would constantly tell anyone who would listen, including you and the media, Robert Mueller was conflicted. Robert Mueller -- Has to go? I never said that. Look, article 2, I'd be allow to fire Robert Mueller assuming I did all of the things that I want to fire him. Number one, I didn't. He wasn't fired. Okay, number one, very importantly. More importantly, article 2 allows me to do whatever I want. Article 2 would have allowed me to fire him. It sounds like -- I wasn't going to fire him. You know why, because I watched Richard Nixon go around firing everybody and that didn't work out too well. Very simply article 2 would allow me to do it. Reporter: Article 2 outlines the powers of the presidency. The president's defenders says he can't commit obstruction of justice while exercising those powers. You talk about article 2. Your position is that you can hire or fire anybody. Stop or start any invest dags -- That's the position of some of the most talented lawyers. You have to have a position like that because you're a president. But without even bringing up article 2 which absolutely gives you every right -- So a president can't obstruct justice? A president can run the country. And that's what happened, George. I run the country. Reporter: When the president does it's not illegal? A president under article 2, it's very strong, read it. Reporter: The president never sat for an interview under oath with the special counsel's team. Instead, he answered written questions about contacts with Russia. But he refused to take any questions about obstruction of justice. But if you answered these questions to me now, why not answer them to Robert Mueller under oath? Because they were looking to get us for lies, for slight misstatements, I looked at what happened to people and it was very unfair. Very, very unfair. Very unfair. So, I'm listening to you, you're not worried about being pros cuted once you leave office. I did nothing wrong. There was no collusion. You don't even hear Russia anymore. Russia's not mentioned. Now it's all about obstruction of what? They built up a phony crime. They hired a man that hated trump. He hired 18 people that were Democrats that hated trump. Some of them contributed to Clinton's campaign. A couple of them worked for Clinton. I mean, what kind of a rigged deal is this? On top of that, after two years, and after being the most transparent in history, I gave them 1.5 million pages of documents, right, I gave them 400, 500 witnesses, I let don mcgahn testify. He was the white house counsel. I let him testify. You didn't answer questions on obstruction. Wait a minute. Wait a minute. I did answer questions in writing. Not on obstruction. I don't know. I answered a lot of questions. They gave me questions I answered them in writing. Not on obstruction. Okay, George, you're being a little wise guy. Okay, which is typical for you. Just so you understand, very simple -- it's very simple. There was no crime. There was no collusion. Now there's no collusion. It was a setup. In my opinion, and I think it's going to come out. I hope it's going to come out -- we're going to find out very soon. I really believe it's going to come out. When you look at strzok, the FBI is the greatest, but the top people were absolutely low lives. When you look at strzok and page, they're talking about an insurance policy just in case she loses that was -- Talk about -- George, I went through the insurance policy. I understand that. But if they were determined to prevent you from becoming president, why wouldn't they leak it beforehand? You know, you'd have to ask them. They tried. They tried. Had that gone out before the election I don't think I could -- I don't think I would have had enough time to defend myself. You clearly believe there was a group of people working against you, do you think president Obama was behind it? I would say that he must have known about it because it went very high up in the chain. You're going to find that out. I'm not going make that statement quite yet. But I'd say that president Obama had to know about it. Reporter: Of course, our conversation took place against the backdrop of growing calls among Democrats for impeachment. You're not worried about what happens in congress? Look, the Republicans in the senate, every single one of them that I see, knows that this is a witch-hunt. They get it 100%. That's what matters. The Democrats are going to do it only because they think it helps them. I think it hurts them in the election. Never a time in our country where someone was so mistreated as I have been and this should never ever be allowed to happen to another president again. A previous administration used the intelligence data, and intelligence agencies to spy on my campaign. You believe that president Obama spied on you? I don't know. We're going to find out. Well, there's a lot to discuss in that interview and the powerhouse roundtable has been here with me and is ready to go over it all of this. And later, my exclusive interview with congresswoman Alexandria ocasio-cortez. Her first Sunday show interview since taking office. And a reminder, tune in for George's full exclusive interview on the ABC news primetime special tonight at 8:00 P.M. Eastern.
This transcript has been automatically generated and may not be 100% accurate.