Billionaire Warren Buffett told CNBC on Monday he would support former New York Mayor Mike Bloomberg if decides to run for president in 2020.

"I think he would be a very good president," Buffett said. "I mean, he and I disagree on some things, but I think that he knows how to run things, I think that he has the right goals for America, he understands people, he understands the market system, and he understands the problems of the people that don't fit well into the market system. I would have no trouble being for him."

Buffett, however, said he is against the idea of former Starbucks CEO Howard Schultz making a bid for the presidency as a third-party candidate.

"If he ran as an independent, I think he would take votes away from any Democrat, including Bloomberg, if he were running," he said. "So, I think it would be a real mistake for him to run, and I think generally third-party candidates are gonna hurt one side or another, and they're more likely to hurt the side that they actually favor because they're closer to that view."

Buffett added third party candidates can actually thwart the will of the people.

Buffett said he is not a card-carrying member of the Democratic Party, although he did say that over the past 30 years he has voted for many more Democratic candidates than Republican ones.

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