NEW YORK ( TheStreet) -- Although Federal Reserve policymakers agree that the economy hasn't changed enough to warrant changes in its plan to buy $600 billion of long-term securities, they disagree on what it would take to make adjustments to the program.

According to minutes from the Federal Open Market Committee's Dec. 14 meeting released Tuesday, some members believed changes to the pace and size of its QE2 stimulus program should depend on economic and financial developments while other members "indicated that they had a fairly high threshold for making changes to the program."

Regarding the increase in Treasury yields following the Fed's QE2 announcement, policymakers said "investors reportedly revised down their estimates of the ultimate size of the FOMC's new asset-purchase program." They also attributed the "backup in yields" to encouraging economic data and the positive impact of a deal on tax cuts.

Critics of the plan, which is to be completed by the end of the second quarter, have pointed to the rise in Treasury yields as a sign that the Fed's program to bolster the economy by keeping interest rates low isn't working.

Overall, committee members felt more confident in the economic recovery since their previous meeting but noted that the slow improvement to price stabilization and unemployment rates continued to warrant expansion of the Fed's holdings of long-term securities.

Members agreed to periodically review both the size and pace of the asset purchase program in light of information regarding the economic outlook, the program's efficacy and any unintended consequences, according to the minutes.

The FOMC's next meeting will be on Jan. 25-26.

-- Written by Melinda Peer in New York.
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