Futures Fall as Greek Rally Fades; Spain Weighs

U.S. stock index futures added to declines Monday as a relief rally in Europe following a victory by pro-bailout parties in Greece's elections proved short-lived and investors turned their focus to ongoing worries over Spain.

European shares were trading mixeddespite Greece’s pro-bailout parties won a narrow victory in Sunday’s election as investors’ attention turned once more to Spain’s beleaguered banking sector.

Financials, the most sensitive sector to worries over the euro zone debt, were trading lower. Citigroup and Morgan Stanley slumped in pre-market trading.

World leaders will meet at a G20 summit in Mexico and are expected to pile pressure on European leaders to find a lasting solution to the euro zone debt crisis.

On the economic front, the National Association of Home Builders (NAHB) will release its monthly housing market sentiment index at 10 a.m. ET.

Facebook shares dipped after the social-networking giant's Chief Technology Officer said he is leaving the company to work on start ups. The company's shares jumped more than 6 percent on Friday, logging the biggest one-day rally since its market debut a month ago.

Barnes & Noble soared ahead of a possible announcement that Microsoft will launch a tablet with the book retailer.

On the M&A front, Extorre Gold Mines skyrocketed after YamanaGold said it will acquire the gold and silver producer in a deal valued around $400 million.

—By CNBC’s JeeYeon Park (Follow JeeYeon on Twitter: @JeeYeonParkCNBC)

On Tap Next Week:

MONDAY: Housing market index, G20 summit
TUESDAY: Housing starts, FOMC meeting begins, Groupon shareholders mtg; Earnings from FedEx, Discover Financial, Adobe Systems
WEDNESDAY: Weekly mortgage apps, oil inventories, FOMG mtg announcement, FOMC forecasts, Bernanke press conference; Earnings from Bed, Bath & Beyond
THURSDAY: Jobless claims, PMI manufacturing index flash, existing home sales, Philadelphia Fed survey, FHFA home price index, leading indicators, Best Buy shareholders mtg, Google shareholders mtg; Earnings from ConAgra, Rite Aid, Oracle
FRIDAY: Earnings from Darden Restaurants

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