The Federal Reserve said Wednesday that it was likely to leave short-term interest rates at rock-bottom levels at least through late 2014, pushing out its easy-monetary policy even further into the future than previously indicated.

In a statement at the end of its two-day meeting, policymakers at the central bank acknowledged the recent improvements in the economy but said that they expected “economic growth over coming quarters to be modest” and the unemployment rate, currently 8.5%, to decline “only gradually.”