President Trump on Thursday escalated his long-running attack on the Federal Reserve, by lashing out repeatedly at the head of the nation’s central bank, Jerome H. Powell, for not doing enough to fortify the economy as the effects of tariffs take hold.

Mr. Trump has long sought to exert control over the politically independent Fed, often denouncing Mr. Powell for keeping interest rates too high for his liking. In an early morning social media post that ricocheted around Washington, Wall Street and beyond, Mr. Trump reprised those attacks, saying: “Powell’s termination cannot come fast enough!”

The president continued his offensive in the afternoon, accusing Mr. Powell of “playing politics.” Speaking from the White House, Mr. Trump said, “If I want him out, he’ll be out of there real fast, believe me.”

Mr. Trump’s broadsides arrived a day after Mr. Powell warned in a speech that the president’s tariffs could create a “challenging scenario” by putting the Fed’s two main goals — stable inflation and a healthy labor market — in tension.

The Fed chairman has maintained that the nation’s central bank must be patient on interest rates — one of the main tools the central bank has to help steer the economy — as it assesses the full impact of the president’s policies on prices. Mr. Powell emphasized on Wednesday that the Fed wanted to ensure that any temporary rise in inflation from tariffs do not become a more persistent problem, in comments broadly interpreted to suggest that the bar for further rate cuts was high.

The president has been pushing for Mr. Powell to cut rates since returning to the White House. The Fed last lowered rates in December and held them steady for two consecutive meetings this year. Traders overwhelmingly expect the Fed to maintain rates at its next meeting in early May.