New Delhi, June 26 -- US President Donald Trump has ramped up his long-standing criticism of Federal Reserve Chair Jerome Powell, launching a fresh round of personal attacks over the central bank's decision to hold interest rates steady.

During a press conference at the NATO summit in the Netherlands on Wednesday, Trump called Powell "an average mentally person" and "a very stupid person," adding: "Low IQ for what he does."

Earlier, he had also labeled the Fed chief "an obvious Trump Hater," claiming Powell's refusal to cut interest rates is costing the US government hundreds of billions of dollars in interest payments.

The US Federal Reserve earlier this month left its benchmark interest rate unchanged at 4.25%-4.50%, citing persisten...