Stock index futures were lower on Friday after equities notched four days of gains and as European policymakers gathered to discuss the region's debt crisis, while Research in Motion weighed on the technology sector after a weak earnings report.

Treasury Secretary Timothy Geithner, at a meeting with European finance ministers in Poland, said the United States and the European Union must work closely together to overcome the current economic challenges. He said Europe has the capacity to contain its sovereign debt crisis, and must avoid loose talk about the euro.

Earlier, a senior euro zone official said Geithner had urged ministers to look at leveraging the 440 billion euro European Financial Stability Facility (EFSF), the bloc's bailout fund, to make it more effective at calming sovereign and banking-system liquidity problems.

With short-term U.S. dollar funding concerns temporarily set aside for European banks, all eyes remain on Greece and the parliamentary votes endorsing a super-sized EFSF, said Peter Boockvar, equity strategist at Miller Tabak + Co in New York.

There still seems to be, though, a complete lack of acknowledgment on the part of most European officials that Greece's finances cannot survive under its current balance sheet and that reforming their economy can only succeed with an extinguishment of part of their debt load.

S&P 500 futures lost 6.5 points and were below 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 were down 46 points, and Nasdaq 100 futures fell 8.75 points.

Research In Motion Ltd reported a steep drop in quarterly profit on limp sales of its smartphones and tablets, and offered investors little hope of a turnaround soon. U.S.-listed shares of RIM fell 19.4 percent to $23.82.

Thomson Reuters/University of Michigan Surveys of Consumers will release preliminary September consumer sentiment index at 9:55 a.m. EDT (1355 GMT). Economists expected a reading of 56.5, compared with 55.7 in the final August report.

Private equity firm Silver Lake is considering a bid for Internet company Yahoo Inc weeks after its chief executive was fired, according to reports.

European shares rose early Friday, adding to gains following central bank action Thursday to boost liquidity.

Stocks advanced for a fourth day on Thursday after coordinated central bank action to add liquidity calmed fears that Europe's financial sector was headed for a credit freeze due to the region's sovereign debt crisis.

(Reporting by Angela Moon; editing by Jeffrey Benkoe)