Buenos Aires, Argentina (CNN) Treasury Secretary Steven Mnuchin tried to soothe fears President Donald Trump is trying to sway the Federal Reserve's plans to raise interest rates this year.

"The administration completely supports the Fed's independence," Mnuchin told reporters Saturday at the start of the G-20 meeting of finance ministers and central bank presidents in Buenos Aires. "Where the Fed ends up on interest rates is one, completely up to them, and [two], is also dependent upon what happens to the economy."

Trump broke with protocol this week by criticizing the Fed's planned interest rate hikes. He tweeted Friday that higher interest rates are taking away America's competitive edge with China. On Thursday, he complained that higher rates were undoing his administration's efforts to help the economy.

"I don't like all of this work that we're putting into the economy and then I see rates going up," Trump said in an interview with CNBC. "Tightening now hurts all that we have done."

Mnuchin said he didn't think it was "a mistake" for the president to weigh in on the Fed's policy decisions, noting Trump watches interest rates closely because of his background as a real estate developer.

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