Washington (CNN) President Donald Trump is on a "fool's errand" with his ongoing trade war with China, Democratic presidential candidate Pete Buttigieg said Sunday.

CNN's Jake Tapper asked the South Bend, Indiana, mayor on "State of the Union" in an exclusive interview why he thinks China would strike a trade deal with him if, as president, he were to ease Trump's pressure and end the President's tariffs imposed on Chinese goods. The US, Buttigieg said, has "a lot of different forms of leverage in the relationship."

"But it's also a fool's errand to think you will be able to get China to change the fundamentals of their economic model by poking them in the eye with some tariffs," he said.

Last year, Trump imposed tariffs on about $250 billion in Chinese-made goods, targeting industrial materials and components. Earlier this month, he said he would add a 10% tariff on an additional $300 billion of Chinese-made products on September 1, which would effectively put a tax on all Chinese goods coming into the United States.

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