But the apparent unanimity among officials belies the very challenging position Mr. Warsh finds himself in now that he is at the helm of the Fed. Mr. Warsh was handpicked for the job by President Trump, who has waged a relentless pressure campaign on the central bank in a bid for lower borrowing costs.

Delivering that has become all but impossible because of the war with Iran and the inflation surge that it has unleashed. A tentative deal has been reached to end the conflict, but the economic blow is poised to be much longer lasting.

Mr. Warsh’s new colleagues have not only rejected the idea that rates can fall anytime soon, but many have also embraced the possibility of having to raise them to bring inflation back to 2 percent — a target they have missed for five years. New projections released alongside Wednesday’s rate decision underscored this shift.

According to the latest “dot plot,” which tracks what policymakers think will happen to borrowing costs over the coming years, roughly half of the officials forecast one or more quarter-point increases from the Fed by year-end. Three people penciled in just one increase, while five thought the Fed would need to raise rates by half a percentage point. One person thought the Fed would need to raise rates by three-quarters of a percentage point.

Eight officials were of the view that rates could remain unchanged by year-end, and only one person penciled in a quarter-point cut.

The dot plot had fewer entries than usual. Mr. Warsh confirmed he was the only official who did not submit any projections, while another policymaker opted against submitting projections just for 2028. Mr. Warsh has argued that Fed officials should speak less frequently and forgo providing specific guidance about where rates may be headed in the near term to avoid limiting their ability to pivot if the economic backdrop changes.

On Wednesday, the Fed significantly scaled back its policy statement and opted to scrap a portion that had previously included a steer on the conditions under which the Fed would consider cutting rates again. It had become problematic for many officials, who preferred more neutral language that conveyed that a rate increase was just as feasible.

This change aligns with Mr. Warsh’s call for less overt communication from the Fed about its next move. But it also likely reflects heightened concern that many officials harbor about the trajectory of inflation, which is running at a three-year high. Even before the war, price pressures were proving unexpectedly sticky in services sectors like hospitality and transportation. A surge in spending related to the proliferation of artificial intelligence and a booming stock market have helped to further turn up the heat.

Rising inflation and a steady policy rate translate to a lower inflation-adjusted or “real” interest rate, meaning the Fed is not restraining the economy as much as it once was. That risks making the Fed’s inflation problem even worse, especially at a time when the labor market has strengthened and the economy more broadly is holding up well.

In their new projections on Wednesday, policymakers substantially raised their forecast for inflation, as measured by the Personal Consumption Expenditures price index, compared with three months ago. They now expect overall inflation to end the year at 3.6 percent and for “core” inflation, which strips out volatile food and energy prices, to register a 3.3 percent pace. As of the latest data in April, P.C.E. inflation accelerated to 3.8 percent compared with the same time last year, while core P.C.E. was up 3.3 percent. The Fed aims for 2 percent inflation.

They also forecast the economy growing at a steady 2.2 percent clip this year and unemployment remaining stable at 4.3 percent.

Mr. Warsh is having to navigate these economic crosscurrents while also trying to make good on his pledge to lead a “reform-oriented” Fed. His priorities include shrinking the Fed’s $6.7 trillion balance sheet and reworking how the central bank both models and measures inflation.