Inflation may not be a concern for the Federal Reserve right now but it could be the "lion in the grass" that takes the central bank by surprise, former Fed governor Robert Heller told CNBC Thursday.
The U.S. central bank on Wednesday started a long-awaited tapering of its asset-purchase program. It said it would cut its monthly stimulus by $10 billion to $75 billion from January and that interest rates would remain low for some time.
(Read more: Fed to taper bond buying by $10 billion a month)
Asked about whether inflation could be a possible risk to the outlook for monetary policy, Heller told CNBC Asia's "Squawk Box": "I think you have it right there, it's the lion in the grass, it's hiding there."
The U.S. consumer price index (CPI) rose 1.2 percent in November from a year earlier. The Fed has a 2 percent inflation target, although it follows a gauge that tends to run a bit below the official CPI.
(Read more: US consumers see flat prices in November)
And the latest Fed statement suggests too-low inflation is more of a concern than high inflation right now. "The Committee recognizes that inflation persistently below its 2 percent objective could pose risks to economic performance," Wednesday's statement read.