Stock index futures were lower on Monday as nagging worries about euro zone sovereign debt continued to weigh on sentiment.

Over the weekend, European finance ministers tried to assure their counterparts in the Group of Seven industrialized nations that the euro zone's debt crisis is under control. They said they would make sure that Greece sticks with its budget-cutting plans.

The risk that the U.S. economy will slip back into recession is lower now than at any time in the past year, U.S. Treasury Secretary Timothy Geithner said Sunday, while conceding that recovery will be slow and uneven.

The CEO of PIMCO, the world's biggest bond fund, voiced concerns about massive U.S. debt levels, saying he preferred to invest in German government bonds rather than Treasuries in the current environment.

S&P 500 futures fell 1.6 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 dropped 4 points, while Nasdaq 100 futures were off 2.75 points.

In equity news, CIT Group Inc said late Sunday it hired former Merrill Lynch Chief Executive John Thain as its new CEO, betting he can guide the commercial lender's post-bankruptcy turnaround.

Citigroup Inc has held talks with private equity groups and hedge funds over the sale of $3 billion in car loans in a move to clear troubled assets from its balance sheet, according to a report in the Financial Times.

U.S. regulators are investigating whether the mortgage insurance market was improperly distressed in 2008 because of the payment demands that Goldman Sachs Group Inc and other banks made on American International Group Inc , The New York Times reported Sunday.

Stocks erased a mid-day drop to end slightly higher on Friday, closing out a volatile week punctuated by mixed signals from labor market data and growing anxiety over the fiscal problems in Europe.

(Reporting by Leah Schnurr; editing by Jeffrey Benkoe)

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