The uncertain outcome of Greece's sovereign debt crisis and its implications for Europe's economy kept U.S. stock futures mixed on Friday, with indexes little changed following two days of steep gains.

Absent any resolution in Europe, traders will focus on the U.S. monthly payrolls report, with non-farm employment expected to have risen by 95,000 jobs last month. A strong number would suggest momentum is building in the world's largest economy.

European shares edged higher after Greece called off a referendum that could have threatened its membership in the euro zone, easing concerns about a Greek default.

The focus on developments from Europe has kept stock trading volatile, with the S&P 500 swinging more than 1.5 percent every day this week. The index is on track to post its first negative week in five after closing on Monday its best month in 20 years.

Just when you think it's safe to get in the water, it's not. Confidence is not high in either direction, said Andre Bakhos, director of market analytics at Lek Securities in New York. This results in fast-paced swings and erratic market behavior.

S&P 500 futures fell 2 points and were below fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration of the contract. Dow Jones industrial average futures gained 5 points while Nasdaq 100 futures lost 8 points.

The White House said U.S. banks' exposure to the euro zone crisis is modest, and the United States can cope if the region's debt crisis grows worse.

In a move to make its deficit targets credible, Italy agreed to have the International Monetary Fund monitor the country's progress with long delayed reforms of pensions, labor markets and privatization. Italy's debt burden could be the market's next target after a resolution of Greece's crisis.

Underscoring continued investor appetite for equities, Groupon Inc raised $700 million in an initial public offering, making it the largest IPO by an Internet company since Google Inc in 2004.

Shares of Starbucks Corp rose in light premarket trading after its quarterly profit beat expectations following strong global sales.

(Reporting by Rodrigo Campos; Editing by Padraic Cassidy)