(Undated) -- Federal Reserve chairman Ben Bernanke says the Fed will keep its target interest rate low after it stops buying $85 billion of bonds every month.

Bernanke said the federal funds rate is likely to remain near zero long after the unemployment rate falls to the Fed's 6.5 percent target for ending the bond-buying program.

He said in a speech to economists Tuesday night that the central bank's policies are helping middle class Americans by supporting housing, strengthening financial markets, and beefing up consumers' cash flows.