WASHINGTON — Federal Reserve officials expressed increasing worries when they met last month, as they grappled with volatile stock markets, trade tensions and uncertain global growth. The threats, they said, made the future path of interest rate hikes “less clear.”

According to minutes of the Fed’s December gathering released Wednesday, officials believed that with inflation still muted, the central bank could afford to be “patient” about future rate hikes. While the Fed did approve a fourth rate increase for the year, the minutes show that a “few” Fed officials argued against hiking rates at the meeting.

The Fed trimmed its projection of possible rate hikes in 2019 from three down to two. But many private economists think the central bank may end up raising rates just once this year if the economy slows significantly.

The minutes said that based on current developments, Fed officials judged that a “relatively limited amount of additional tightening would likely be appropriate.”

The minutes covered the Dec. 18-19 meeting at which the central bank raised its benchmark rate for the fourth time in 2018, pushing the policy rate to a range of 2.25 percent to 2.5 percent.

Many private economists think the central bank may end up raising rates just once this year if the economy slows significantly.

Financial markets were not pleased, and stocks falling sharply. The drop was blamed in part on comments Federal Reserve Chairman Jerome Powell made at a news conference following the announcement in which he seemed to emphasize the strength of the economy more than possible downside risks.

However, in an appearance last Friday, Powell struck a somewhat different tone, stressing that with inflation remaining muted, the Fed could afford to be “patient” in determining when to hike rates this year. The minutes delivered a similar message.

Powell is scheduled to speak again on Thursday before the Economic Club of Washington in remarks that will be closely watched for further clues about the Fed’s current thinking.

“There is no pre-set path for policy,” Powell said in his Atlanta comments, which helped to send the market up by 746 points last Friday. “With the muted inflation readings we have seen coming in, we will be patient as we watch to see how the economy evolves.”

The minutes made no reference to any of the attacks President Donald Trump has leveled at Powell and the Fed for the series of rate hikes, which Trump has blamed for pushing the stock market down.

The minutes cited rising concern among business contacts about the impact of Trump’s get-tough trade policies, which have imposed punitive tariffs on imports from China and other nations in an effort to trim America’s huge trade deficit.

The minutes were released with the usual customary three-week lag since the meeting.