Image copyright Getty Images Image caption Most observers do not believe the Fed will increase interest rates until this summer at the earliest

Officials at the Federal Reserve are unlikely to raise interest rates soon, the latest minutes from the bank's January meeting have revealed.

Policymakers worried about lower-than-expected inflation as well as slow wage growth in the US economy, the world's largest.

The Fed has kept its benchmark interest rate at zero since late 2008, when it slashed rates to boost the economy.

Most observers do not expect a rate rise before this summer.

"Many participants indicated that their assessment of the balance of risks associated with the timing of the beginning of policy normalization had inclined them toward keeping [rates at zero] for a longer time," the minutes said.

Although the US economy has been growing at a healthy rate, sluggish growth abroad combined with slower-than-expected wage increases have made policymakers wary of raising rates and unnecessarily stifling economic growth.

During the meeting, officials were concerned about developments abroad, including the war in Ukraine, a slowdown in China's economy and continued negotiations between Greece and its creditors.

They were further concerned that markets might be inclined to overreact should the Fed drop language from its statement indicating that it could be "patient" in raising rates, adding to a decision to move at a slower pace.