Rate-rise discussion 'should begin mid-year'

Federal Reserve official says that US monetary policy will remain 'extremely stimulative'

Federal Reserve Bank of San Francisco President John Williams said a discussion should happen mid-year about tightening policy, even as he lowered his economic growth forecast.

Williams, who votes on policy this year, said in remarks prepared for delivery on Tuesday that he expects US real gross domestic product to grow about 2.5 percent in 2015 from a previous forecast of just under 3 percent. He said he expected an improving economy to push wages and prices up, and inflation to move back toward the Fed's 2 percent target.