Billionaire investor Warren Buffett urged Americans to rally around Donald Trump, saying the president-elect "deserves everybody's respect."

"I support any president of the United States. It's very important that the American people coalesce behind the president," Buffett said in an interview with CNN.

"That doesn't mean they can't criticize him or they can't disagree with what he's doing maybe. But we need a country unified," Buffett added.

"You have to choose between two people and I chose Hillary," saying that her temperament was the number one reason why he endorsed and voted for her. Buffett said he understands why Trump won. Many Americans are resentful about the wealth gap in the country.

Meanwhile, thousands took to the streets Saturday across the United States as demonstrations against Trump continued in New York, Chicago, Los Angeles and beyond.

Protesters rallied at New York's Union Square before picking up steam and taking their cause toward Trump Tower. Police set up barricades in front of some of the most expensive stores in Manhattan as the group made its way along Fifth Avenue, the AP reported.

Protests were mainly peaceful, but in Portland, Oregon, a man who was participating in a march was shot after a confrontation with someone in a vehicle. Police expect the man to survive and detained four people in connection with the shooting. A motive for the shooting was unclear. The four people detained are believed to be gang members, but the victim is not.

For his part, Buffett said he was skeptical of some of Trump's claims about how fast he can grow the economy. "Nobody can grow the economy 4% in real terms over time," Buffett said, referring to a Trump campaign promise. "The math is too extraordinary."

But Buffett thinks that even 2% annual growth over a period of a few years will lead to wage growth and gains in the stock market.

Buffett said he's not worried about Trump trying to enact some of the more controversial things that he talked about in his campaign, such as cracking down on immigration and enacting isolationist trade policies.

"There are a lot of things said in campaigns that don't happen after the election," he said.

Asked about Trump's proposal to impose 35% tariffs on goods imported to the U.S. -- Buffett said: "It's a bad idea, a very bad idea, but I'm not going to say it is going to cause a recession."

He also expects stocks to continue to rise under the billionaire real-estate tycoon's term as president of the United States.

"The stock market will be higher 10, 20 and 30 years from now and it would have been with Hillary [Clinton] and it will be with Trump," Poppy Harlow.

Any suggestion they will begin to plunge in the wake of Trump's surprise victory on Tuesday is "silly," the CEO of Berkshire Hathaway added. 

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