Underscoring divisions at the U.S. central bank, one top policymaker on Friday said he had cut his forecast for economic growth, even as another said he saw no economic need for new monetary stimulus.

On Tuesday, the Federal Reserve reinforced its commitment to super-easy monetary policy by promising to keep benchmark interest rates near zero through mid-2013.

The central bank also said it was weighing other options to help strengthen a weak economic recovery. Three Fed officials cast their vote against the decision, the first triple dissent at the Fed since 1992.

In an unusual statement Friday defending his dissent, Minneapolis Fed Bank President Narayana Kocherlakota said that higher inflation and lower unemployment since the Fed had last eased policy meant that doing more was unnecessary.

I do not believe that providing more accommodation -- easing monetary policy -- is the appropriate response to these changes in the economy, Kocherlakota said in the statement, posted on the Minneapolis Fed's website at: http://www.minneapolisfed.org/publications_papers/pub_display.cfm?id=4715

While unemployment is still disturbingly high, he said, the evolution of macroeconomic data did not reflect a need to make monetary policy more accommodative than in November 2010, when the Fed embarked on a $600 billion bond-buying program that ended this past June.

Inflation as measured by the Fed's preferred core PCE price index rose to 1.3 percent in the 12 months ended in June, from a low last December of 0.9 percent. Unemployment fell to 9.1 percent in July, down from just over 10 percent at its peak last year.

DUDLEY DEFENDS FOMC

However, speaking in New York at a media briefing, New York Fed President William Dudley, who on Tuesday cast his vote in favor of current easy monetary policy, emphasized the disappointing economic growth in the first half of 2011.

While he said he does not expect a double-dip recession, Dudley suggested that headwinds like a worsening jobs market, flat household spending, and a depressed housing sector would keep growth from picking up strongly in the second half.

Dudley's assessment appeared to be in line with the majority of the Federal Open Market Committee, which on Tuesday said downside risks to the recovery justified further policy easing.

The statement issued by the FOMC earlier this week presents a sober assessment of the state of the U.S. economy, Dudley said.

He didn't expand on Fed policy, but said after Tuesday's statement market interest rates generally moved lower which should help provide some additional support for economic activity and jobs.

A week ago traders said they did not expect the Fed to raise rates until the first quarter of 2013. Now they have pushed that timeframe back to September 2013.

As president of the New York Federal Reserve, Dudley is one of the central bank's most influential policymakers alongside Chairman Ben Bernanke and Vice Chair Janet Yellen.

Kocherlakota, among the newest of the Fed's roster of policymakers, was joined in dissent on Tuesday by two other regional Fed bank presidents, Dallas Fed President Richard Fisher and Philadelphia Fed President Charles Plosser. Neither have provided any details on the reasons for their dissent.

It is unclear whether the high level of discord at the Fed over policy will restrain Bernanke from moving forward with further easing should the economy worsen further. Recent economic data is mixed, with U.S. consumer sentiment worsening sharply in early August, but retail sales posting their biggest gains in three months in July.

Kocherlakota said he issued his statement as part of his commitment to transparency, which he called an essential part of policy formation. He declined to comment beyond the statement.

The policymakers spoke at the close of a volatile week on Wall Street after Standard and Poor's downgrade last week of U.S. government debt and ongoing concerns over Europe's debt crisis.

Thursday was the fourth day in a row the S&P 500 ended with a move of more than 4 percent, and the index has fallen for 11 of the past 14 days.

Calling the conditions unsettled, Dudley said Standard and Poor's downgrade of the U.S. government's credit rating last Friday was a shot across the bow and will help reinforce the commitment to long-term fiscal consolidation.

(Reporting by Edith Honan, Kristina Cooke, Glenn Somerville, Ann Saphir)