Most economists believe the Federal Reserve's bond-purchase program is helping to support U.S. growth, though many remain skeptical, a survey released on Monday found.

The survey from the National Association for Business Economics found 62.4 percent of the economists polled think the central bank's $600 billion stimulus plan is working.

Another 21.8 percent see the policy, which has come under fire from some conservative politicians and a number of emerging market policy makers, having no impact. Another 15.8 percent said the program was actively harmful.

In response to the deepest recession in generations, in addition to slashing interest rates to zero, the Fed bought over $2 trillion in government and mortgage bonds in an effort to keep long-term borrowing costs down.

With inflation fears suddenly emerging after months of worries about deflation, analysts are beginning to ponder the possibility that the Fed may have to tighten policy over the next year.

While more than half of the survey respondents indicate that current monetary policy is about right, there is also a sense that overall monetary policy will become more restrictive, NABE said.

The discord deepened when the 263 NABE members were asked whether the current level of monetary accommodation is appropriate. Just over half said policy is just right where it is, while 40.9 percent felt it was too stimulative.

With the U.S. expansion apparently picking up steam in recent weeks, some of the more vocal inflation hawks at the Fed have said the central bank should consider whether to cut short the latest $600 billion bond-buying plan.

However, most policy makers, including Fed Chairman Ben Bernanke, appear inclined to complete the planned purchases by the scheduled June deadline.

Asked about the likely trajectory of prices in the U.S. economy over the next three years, 40 percent of respondents said the risk of inflation was greater than the risk of deflation. Eighteen percent saw deflation as the bigger danger, while 36 percent said neither outcome was very probable.

The survey was conducted between January 28 and February 14, before a wave of pro-democracy protests and political unrest overtook parts of North Africa and the Middle East, pushing oil prices above $100 a barrel.

Recent data has shown the U.S. economy strengthening.

A report on Friday showed unemployment fell to a nearly two-year low of 8.9 percent in February as hiring hit the fastest pace in nine months. Still, the level of unemployment is historically high and most Fed officials feel the economy is still in need of support.

(Reporting by Pedro Nicolaci da Costa; Editing by Leslie Adler)

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