Federal Reserve officials expressed renewed worry about financial-market turbulence and slow economic growth abroad, leaving doubts about whether the central bank will raise interest rates as early as March.

The U.S. central bank lifted short-term interest rates by a quarter percentage point in December and penciled in four more increases this year.

But the policy statement, released Wednesday after a two-day meeting, raised questions about whether the Fed would follow through with a rate move when it gathers again on March 15-16. Futures markets place just a 25% probability on rate increase by then. The central bank sought to keep its options open while it assesses a potentially shifting economic landscape.

The plan to raise rates was built on officials’ expectations the economy would continue strengthening, but the statement suggested they now aren’t so sure: “The [Fed] is closely monitoring global economic and financial developments and is assessing their implications for the labor market and inflation, and for the balance of risks to the outlook.”

That line caught the attention of investors and underscored the Fed’s newly uncertain tone. At their December meeting, officials expressed confidence the job market was improving and inflation would rise toward their 2% goal. Now officials are wondering whether they will need to revise down their projections for inflation, growth and hiring when next they meet.
An even-more striking statement of uncertainty is that the Fed wouldn’t offer an assessment about risks to the economic outlook. To guide markets, officials normally say whether risks to the outlook are balanced, or tilted toward economic strength or weakness. Officials abandoned any such assessment this time around.

“Fed loses its balance,” was the headline that J.P. Morgan Chase economist Michael Feroli sent out to clients after the meeting. He noted the Fed has rarely punted on its risk assessment. One time included September 2007, at the dawn of the 2007-2009 financial crisis; another in March 2003, when the U.S. was preparing to invade Iraq and oil prices were surging.

“I don’t think they’ve made up their mind about March,” said Gus Faucher, senior economist at PNC Financial Services Group. “They want to see how conditions play out over the next month and a half.…I don’t think it’s a done deal one way or another at this point.”

Stocks tumbled following the meeting, after being little-changed for the day to that point. The Dow Jones Industrial Average fell 222.77 points, or 1.38%, to 15944.46; it is now down 8.5% for the year. U.S. Treasury bond prices rose after the meeting, reversing earlier losses and sending their yields lower. The dollar was little changed.

For now the Fed is keeping its benchmark short-term interest rate steady between 0.25% and 0.5%. Officials are sticking to a forecast that the U.S. economy will continue to grow modestly, produce jobs and gradually lift inflation to 2%.

The Chinese economic slowdown and global market tumult could be temporary stumbles or signs of deep and enduring problems. The Fed has been wrestling with these doubts since August, when China’s stock declines and currency devaluation set off a global market rout. Fed officials hesitated then about raising rates. After markets settled, they moved in December, and now new turbulence has placed central-bank officials back in the tough spot of measuring up new threats to the economy.

“A further deterioration in the data or financial markets could prompt a delay in rate hikes while an improvement in the data and a stabilization of financial markets would open the door for a second rate hike in March,” Barclays chief U.S. economist Michael Gapen said.

While the Fed in December said it expected four quarter-percentage-point interest-rate increases this year, investors and traders believe there will be fewer. If the Fed follows through on its tentative plan, rates would rise to 1.375% by year-end; futures markets put the expected rate at 0.605% in December, meaning just one more rate increase this year, and even that isn’t a sure thing.

The policy statement pointed to the mixed economic backdrop that confronts Fed Chairwoman Janet Yellen, who is slated to testify before Congress in February.

“Labor market conditions improved further even as economic growth slowed late last year,” the Fed said. While job gains were strong, it said, consumer spending and business investment were just moderate and net exports soft. Some of the fourth-quarter slowdown resulted from businesses reducing inventories, a development that should be temporary because eventually inventories will stabilize or even rise.

The Fed is also trying to assess a shifting inflation outlook. Officials said they expected it to remain low in the near term, thanks to new declines in energy prices, but to gradually rise. They have been watching core inflation closely, which tracks consumer prices excluding volatile food and energy prices, and these measures have been firm and possibly rising.

“I take it as a positive sign that the [core inflation] rate…has been quite stable despite the downward pressure being exerted by lower energy prices on the prices of nonenergy goods and services, as well as the drop in nonenergy import prices from a firmer dollar,” New York Fed President William Dudley said in a speech earlier this month.

However, some officials worry that market expectations for future inflation are shifting down, a sign investors don’t believe the Fed will reach its 2% target anytime soon.

The Fed asserted it has little patience for a long run of very low inflation. In a statement of its long-run goals, released with its policy statement, it emphasized it wouldn’t tolerate inflation that is either persistently below its 2% objective or above it. Long-run deviations from the target were a concern, the statement said. Inflation has run below the Fed’s goal now for more than 3½ years.

The main challenge for officials at their latest meeting was deciding how to signal their degree of concern about the market turbulence that greeted 2016 and new signs of a China’s slowdown.

In September, after concerns about China roiled markets in late summer and early fall, Fed officials said these developments could restrain economic activity and push down inflation.

On Wednesday they stopped short of repeating that declaration, which would have suggested their economic forecasts were already souring in light of the market developments. Instead they said they were watching events closely, an echo of language they used in October, which preceded the rate increase.

By being noncommittal, the Fed is effectively keeping its options open. Officials likely want to assess the tone of economic data and market developments between now and the March meeting before deciding what signal to send about the path of rates.