The Omicron variant of the coronavirus comes at a challenging moment for the Federal Reserve, as officials try to pivot from containing the pandemic’s economic fallout toward addressing worryingly persistent inflation.

The central bank has spent the past two years trying to support a still-incomplete labor market recovery, keeping interest rates at rock bottom and buying trillions of dollars’ worth of government-backed bonds since March 2020. But now that inflation has shot higher, and as price gains increasingly threaten to remain too quick for comfort, its policymakers are having to balance their efforts to support the economy with the need to keep price trends from leaping out of control.

That newfound focus on inflation may limit the central bank’s ability to cushion any blow Omicron might deal to America’s growth and the labor market. And in an unexpected twist, the new variant could even speed up the Fed’s withdrawal of economic support if it intensifies the factors that are causing inflation to run at its fastest pace in 31 years.

“In every one of the previous waves of the virus, the Fed was able to react by effectively focusing on downside risks to growth, and trying to mitigate them,” said Aneta Markowska, chief financial economist at Jefferies. “They’re no longer able to do that, because of inflation.”

said in an interview last week.

Janet L. Yellen, the Treasury secretary and a former Fed chair, made similar remarks at an event on Thursday.

“The pandemic could be with us for quite some time and, hopefully, not completely stifling economic activity but affecting our behavior in ways that contribute to inflation,” she said of the new variant.

during congressional testimony last week. “I think the risk of higher inflation has increased.”

Fed officials initially expected a 2021 price pop to fade quickly as supply chains unsnarled and factories worked through backlogs. Instead, inflation has been climbing at its fastest pace in more than three decades, and fresh data set for release on Friday are expected to show that the ascent continued as a broad swath of products — like streaming services, rental housing and food — had higher prices.

Given that, Mr. Powell and his colleagues have pivoted to inflation-fighting mode, trying to ensure that they are poised to respond decisively should price pressures persist.

Mr. Powell said last week that officials would discuss speeding up their plans to taper off their bond-buying program — prompting many economists to expect them to announce a plan after their December meeting that would allow them to stop buying bonds by mid-March. The Fed announced early in November that it would slow purchases from $120 billion a month, making the possible acceleration a notable change.

Ending bond-buying early would put officials in a position to raise their policy interest rate, which is their more traditional and more powerful tool.

nearly four million people are still missing from the labor market compared with just before the pandemic began. Some have most likely retired, but surveys and anecdotes suggest that many are lingering on the sidelines because they lack adequate child care or are afraid of contracting or passing along the coronavirus.

If the Fed begins to remove its support for the economy, slowing business expansion and hiring, the labor market could rebound more slowly and haltingly when and if those factors fade.

But the balancing act is different from what it was in previous business cycles. The factors keeping employees on the sidelines right now are mostly unrelated to labor demand, the side of the equation that the Fed can influence. Employers appear desperate to hire, and job openings have shot up. People are leaving their jobs at historically high rates, such a trend that job-quitting TikTok videos have become a cultural phenomenon.

In fact, the at-least-temporarily-tight labor market is one reason inflation might last. As they compete for workers and as employees demand more pay to keep up with ballooning consumption costs, companies are raising wages rapidly. The Employment Cost Index, which the Fed watches closely because it is less affected by many of the pandemic-tied problems that have muddied other wage gauges, rose sharply in its latest reading — catching policymakers’ attention.

If companies continue to increase pay, they may raise prices to cover their costs. That could keep inflation high, and anecdotal signs that such a trend is developing have already cropped up in the Fed’s survey of regional business contacts, called the Beige Book.