Stock index futures were little changed on Friday as a retreat in commodity prices weighed on natural resource shares after the U.S. dollar rebounded.

The U.S. dollar rose broadly after Federal Reserve Chairman Ben Bernanke said that monetary policy might have to be tightened as a recovery takes hold.

The dollar's decline, which culminated into a 14-month trough against a basket of currencies on Thursday, has been one the major underpinnings of the stock market's run-up as the appetite for riskier assets grew.

U.S. front-month crude slipped 47 cents to $71.22 a barrel, while gold eased after hitting records for three straight sessions.

Among natural resources shares, Freeport-McMoran Copper & Gold Inc slipped 0.3 percent to $74.79 in light volume before the bell.

But shares of Research In Motion Ltd , a maker of BlackBerry devices, rose 1 percent to $69.35 following a broker upgrade.

S&P 500 futures dipped 1.20 points but were a tad above fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures shed 13 points, and Nasdaq 100 futures fell 4 points.

U.S. stocks rose for a fourth straight session Thursday as a surprising quarterly profit from Alcoa Inc got third-quarter earnings off to a strong start.

(Reporting by Ellis Mnyandu; editing by Jeffrey Benkoe)