Stock index futures pointed to a flat open 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.

Worries about Greece's financial problems and their potential to spread to other euro zone countries or beyond has taken the steam out of Wall Street's rally in recent weeks.

It's difficult enough for investors to digest when companies can't meet obligations. When countries can't meet their obligations, it sends more pronounced shivers through the market, said Andre Bakhos, president of Princeton Financial Group in North Brunswick, New Jersey.

It hurts sentiment in the fact that the underlying global fundamentals remain shaky.

Shedding more light on the U.S. economy, Treasury Secretary Timothy Geithner said Sunday the risk that it will slip back into recession is lower now than at any time in the past year, but he said that recovery will be slow and uneven.

Even so, debt concerns remained in the spotlight. The chief executive 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.

S&P 500 futures rose 2.5 points but were about even with 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 rose 19 points, while Nasdaq 100 futures were up 3.75 points.

CIT Group Inc said late Sunday it hired former Merrill Lynch Chief Executive John Thain as its new CEO to guide the commercial lender's post-bankruptcy turnaround.

CVS Caremark Corp reported a higher quarterly profit, helped by improved sales at its drugstores. The shares rose 2.2 percent to $31.76 in premarket trade.

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.

(Editing by Padraic Cassidy)