President Donald Trump said in an interview airing Thursday that he has a "very good relationship" with China's President Xi Jinping, but at the same time, "we could cut off the whole relationship" with the Asian nation. 

"If you did, what would happen, you'd save $500 billion if you cut off the whole relationship," Trump told Fox Business' Maria Bartiromo. "I said this for years, I said it with other countries also. China's not the only country ripping us off. At NATO, where we defend Europe for nothing, by the way, essentially nothing, I was able to get them to pay hundreds of billions of dollars more."

Meanwhile, China "could have stopped" the coronavirus pandemic at its source, said Trump, adding that he doesn't know if a decision was made to allow that to happen, but it "more likely got out of control."

"Here's what I know for sure," he said. "They didn't allow people to go into China. But they did allow them to go out to the world including the United States. That's why Europe is a mess. Look at these countries. Russia's having a hard time. Everybody's having a hard time."

Some of the countries are just starting the coronavirus process, he added, but the United States is getting toward the end" of it. 

And even though China started cornering the market on personal protection equipment, "that's not the big thing," said Trump. 

"The big thing is they should have never let this happen," said Trump. "I make a great trade deal and now I say it just doesn't feel the same to me. The ink was barely dry and the plague came over, and it doesn't feel the same to me."

He said he's heard that China would like to renegotiate the deal reached in January, but the United States won't do that.

"Everything I said turned out to be right," he said. "You go back 10 years, 20 years, I'm telling you, it's why I'm sitting here, the beautiful Oval Office because of trade. Not only China but other countries also. Other countries, they charge us tariffs to do business and we're not allowed to charge them."

Meanwhile, the United States has "lost a fortune in dealing with China," but other presidents have "allowed them to rip us off like you've never seen before."

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