The US Federal Reserve will raise interest rates again in the next three months, according to two-thirds of economists polled by Reuters.

But many say rates will not rise as quickly next year as policymakers have suggested. 

The Fed increased rates for the first time in nearly a decade this week, confident the US economy can stand higher borrowing costs after years of stimulus and near-zero rates.

Janet Yellen, who chairs the rate-setting Federal Open Market Committee, made clear future increases would be gradual. 

Considering the muted outlook for inflation and oil prices, a strong dollar hurting US manufacturers, and the continued fragile state of the global economy, the Fed may have to be cautious with future rate hikes. 

77 of 120 economists in a snap poll conducted a couple of days after the meeting, said rates will next move higher by March. And all others but two said it would happen in the second quarter.

Fed policymakers currently estimate rates at 1.25-1.5% by the end of 2016, 100 basis points higher than the current rate. The median forecast among economists polled by Reuters, however, is that the fed funds target rate would be 1-1.25% by then. 

The most hawkish prediction in the poll is that rates would reach 1.75-2% by the end of next year and the most dovish said the Fed will not hike rates again at all in 2016.  

The risk, however, is that inflation fails to rise as predicted. Core PCE inflation, which the Fed watches closely, is forecast around 1.5-1.7% during 2016 - similar to what Fed policymakers expect, but lower than the 2% target. 

With oil prices likely to stay low through next year, those expectations may be optimistic. That is especially true considering the strong dollar, which is predicted to remain firm, makes imports cheaper in the US. 

The outlook for US growth is also tame, expected at a steady 2.4-2.5% annualised pace in each quarter over the coming year.