Mr. Mnuchin has worked in recent days to obtain Mr. Trump’s assurance that he would not remove Mr. Powell, according to an administration official who spoke on condition of anonymity. But that person cautioned that Mr. Trump could change his mind. The person noted Mr. Trump has a tendency to nurse grudges even when he temporarily sets a subject aside.

Mr. Mnuchin has been under pressure from Mr. Trump to stabilize markets, which are on pace for the largest December declines since the 1930s. In a statement Sunday, Mr. Mnuchin said he had contacted the chief executives of six major banks to make sure their operations were running smoothly.

Mr. Mnuchin, who made the calls while on vacation in Cabo San Lucas, Mexico, said that bank executives confirmed they had sufficient liquidity for lending and market operations — the kind of statement the government usually reserves for moments of genuine uncertainty about the health of the financial system. The statement added that Mr. Mnuchin would convene a meeting of the President’s Working Group on financial markets, which he leads, to coordinate efforts to “assure normal market operations.”



The Fed’s unanimous decision to raise its benchmark interest rate on Wednesday reflected the confidence of its officials that the economy remains strong — even as they insisted that future rate increases would depend on continued growth. By raising rates, the Fed is bringing to a close its long campaign of economic stimulus that began during the 2008 financial crisis, which included lowering interest rates to near zero.

Still, Mr. Trump is hardly alone in his opposition to the Fed’s move. Some economists argue the Fed should continue its stimulus campaign to drive up employment and wages. They note that the Fed is about to undershoot its 2 percent inflation target for the seventh consecutive year, suggesting there is no need to step on the brakes.

Many investors had also wanted a pause, and the decision set off another slide in stock prices.

But even investors who disagreed with Wednesday’s decision generally do not want politicians to play a larger role in Fed policymaking, preferring to leave the management of interest rates primarily in the hands of technocrats. Most developed nations have granted their central banks considerable autonomy over policymaking precisely because of concerns that politicians would seek to increase short-term growth at the expense of inflation and instability.

In fact, during his presidential campaign, Mr. Trump accused the Fed of getting political, saying that the bank’s chairwoman at the time, Janet L. Yellen, should be “ashamed” for keeping interest rates low — a move he said was meant to help President Barack Obama.