Washington (CNN) President Donald Trump continued to criticize Federal Reserve Board chairman Jerome Powell during a phone interview Wednesday with Fox Business.

Powell "should've never raised the rates," Trump said, claiming that his hand-picked Fed chair is "trying to prove how tough he is."

"He's trying to prove how tough he is 'cause he's not going to get pushed around," Trump said, adding, "Nobody ever heard of him before."

Powell, he said, is "not doing a good job."

Powell on Tuesday hailed the independence of central banks.

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