Narayana Kocherlakota, president of the Federal Reserve bank of Minneapolis, said the central bank could spur economic growth by clarifying the conditions that would prompt a wind down of the Fed's asset purchases. 

"Monetary policy should be more accommodative,' Kocherlakota said

He added, "The FOMC could reduce the public’s level of policy uncertainty by clarifying the nature of the economic conditions that would lead the Committee to reduce or stop its current asset purchases."