Federal Reserve officials offered new warnings Friday that they could raise interest rates again and hold them at higher levels for longer to return inflation to the central bank's 2% target.

Fed Governor Michelle Bowman said inflation remains too high despite considerable progress, and she continues to expect to raise rates further and hold them at a restrictive level for some time.

"We should remain willing to raise the federal funds rate at a future meeting if the incoming data indicates that progress on inflation has stalled or is too slow to bring inflation to 2% in a timely way," Bowman said in a speech at the Independent Community Bankers of Colorado in Veil, Colo.

Bowman expects inflation to stay above the Fed’s target of 2% at least until the end of 2025, underscoring that progress is likely to be slow and will require more work.

Read more: What the Fed rate-hike pause means for bank accounts, CDs, loans, and credit cards

Another Fed official, Boston Fed President Susan Collins, echoed Bowman's hawkish approach, saying she favors one more rate hike this year and warning that more tightening may also be possible.

"I expect rates may have to stay higher, and for longer, than previous projections had suggested, and further tightening is certainly not off the table,” Collins said in a speech in Boston.

The Fed opted to hold rates steady at its interest rate meeting this week in the range of 5.25%-5.5%. Officials projected one more rate hike this year and see fewer rate cuts over the next few years than previously thought, implying the central bank intends to hold rates at higher levels for longer.

The Fed has raised rates 11 times since March 2022 in its most aggressive rate-hiking campaign since the 1980s. Inflation, while down from its peak, remains double the Fed’s inflation target of 2%.

Elsewhere, another Fed official took a more neutral approach in her new comments Friday. San Francisco Fed President Mary Daly said while inflation is coming down without a large disruption in the job market, it’s “far too early to declare victory.”

“We need to see if more is necessary or if we can simply hold where we are,” Daly said during a fireside chat in Phoenix. “What we did at the meeting this week is not a predictor of what we'll do at the next meeting. It's just a sign that as we get closer to our destination of where we will peak the rate, we need to go at a slower pace.”

Daly also noted that the Fed is trying to bring inflation back down as “gently” as possible, toeing the line of not causing a recession. Like other Fed officials, Daly thinks it unlikely that inflation will reach the Fed’s 2% target next year, implying more work.

Collins said it’s too soon to be confident that inflation is on a sustainable path back to the Fed's target. She cited inflation in core services excluding shelter, which accounts for over half of the Fed’s preferred core inflation measure, that has yet to show sustained improvement.

Collins also indicated that this time it may take longer to feel the full effect of the Fed’s rate hikes since the rate-hiking campaign occurred when households were flush with cash.

Now that cash levels are coming down, Collins said business and household spending is likely to become more sensitive to higher rates, helping to temper demand growth and realign it with supply.

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