WASHINGTON, Feb. 24 (Xinhua) -- The U.S. Federal Reserve Chairman Ben Bernanke said Wednesday that record-low interest rates are still needed to boost the economic recovery and to tackle the high unemployment.

The central bank continues to anticipate that economic conditions -- including low rates of resource utilization, subdued inflation trends, and stable inflation expectations -- are likely to warrant exceptionally low levels of the federal funds rate for an extended period, Bernanke said in his semiannual monetary policy report to the Congress.

"Over the past year, the Federal Reserve has employed a wide array of tools to promote economic recovery and preserve price stability," Bernanke said.

The federal funds rate, the leading rate, has been maintained at a historically low range of 0 to 1/4 percent since December 2008.

Federal Reserve Chairman Ben Bernanke looks up during his meeting with Senator Dick Durbin (D-IL) to discuss Federal Reserve policy and Bernanke's upcoming confirmation vote Capitol Hill in Washington January 25, 2010

The Fed chief said that the U.S. economy expanded at about a 4 percent annual rate during the second half of last year. Private final demand does seem to be growing at a moderate pace, buoyed in part by a general improvement in financial conditions.

The central bank anticipates a moderate pace of economic recovery, with economic growth of roughly 3 to 3-1/2 percent in 2010 and 3-1/2 to 4-1/2 percent in 2011.

However, "the job market has been hit especially hard by the recession," as employers reacted to sharp sales declines and concerns about credit availability by deeply cutting their workforces in late 2008 and in 2009.