The Federal Reserve may need to scale back its $600 billion Treasury bond-buying program if the economy grows more quickly than expected, a Fed official said Tuesday. Charles Plosser, president of the Federal Reserve Bank of Philadelphia and a voting member this year on the Fed's main policymaking group, worries that the Fed's program may soon "backfire on us" and encourage inflation if "we don't begin to gradually reverse course." Plosser has repeatedly spoken out against the bond-buying program. He has raised concerns that the risks - namely the potential for unleashing inflation - could outweigh any benefits to the economy. Plosser was not a voting member when the Fed adopted the program on November 3, although he attended the meeting. Only five of the 12 regional presidents get a vote. The regional bank president, who has been outspoken with his concerns about inflation, is likely to put pressure on Federal Reserve Chairman Ben Bernanke and his colleagues to shrink the program. The Federal Reserve has left open the door to buying less government debt if the economy were to strengthen more than anticipated or buy less were if to weaken. The Fed meets next on January 25 to 26 and will review the program at that time.