Forward guidance from the U.S. Federal Reserve has been vague and the central bank should ensure its guidance on monetary policy is real, says one Nobel prize-winning economist.



The Fed as well as the European Central Bank and Bank of England have adopted 'forward guidance' at their policy meetings to give financial markets greater clarity on the outlook for monetary policy.

While this is a good idea in theory, the reality has proved different, Lars Peter Hanson, a professor at the University of Chicago, told CNBC Asia's "Squawk Box" Wednesday.

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"Forward guidance was meant to be a clear statement from the Fed about when it would change interest rates. That was the original rational," said the economist, who was a joint winner of the 2013 Nobel Prize in economic sciences.

"It seems that the commitments have been more and more vague and been open to more and more contingencies and it's opened the door to more and more discretion. That's one way you add more uncertainty to the economic environment," he added.