U.S. stock index futures pointed to a flat to slightly higher open for Wall Street on Thursday, with futures for the S&P 500, for the Dow Jones industrial average and for the Nasdaq flat to up 0.1 percent by 0913 GMT.

Trading was expected to be volatile due to the expiry of index and individual stock futures and options, known as quadruple witching.

Investors will be keeping an eye on developments in the euro zone, as European Union leaders meet on Thursday to try to agree the next steps in tackling a year-long debt crisis that has consumed Greece and Ireland and threatens to spread to Portugal and Spain.

U.S. stocks suffered a third straight late-day sell-off on Wednesday, suggesting it may be difficult to chalk further gains as the year comes to a close.

In company news, firms scheduled to release quarterly corporate results include Oracle and FedEX

BP is expected to be in focus, after the Obama administration on Wednesday launched a legal battle against the oil major and its partners by suing them for the worst offshore oil spill in U.S. history, which could cost the companies billions of dollars.

Citigroup Inc will officially open a new, high-tech branch in New York City on Thursday, in an effort to woo more business from wealthy, urban customers.

The U.S. aerospace industry is headed for continued sales growth in 2011, but warplanes are likely to play a smaller role than in recent years due to possible Pentagon cutbacks, the industry's main trade and lobbying group said on Wednesday.

Google Inc's YouTube is in talks to buy Web show maker Next New Networks in what would be the video sharing site's first foray into content production, the New York Times reported on Wednesday.

A deal that President Barack Obama struck with Republicans to extend tax cuts for nearly every working American and spur job growth moves to the U.S. House of Representatives for passage as early as Thursday.

The market is likely to get some direction from weekly U.S. jobless claims figures at 1330 GMT, with investors looking for further signs of the labor market's health.

Also of interest at 1330 GMT will be U.S. housing starts data.

In Europe, the pan-European FTSEurofirst 300 <.FTEU3> index of top shares was up 0.3 percent at 1,130.62 points, though gains were limited by falls in heavyweight BP and Tansocean .

(Reporting by Harpreet Bhal; Editing by Mike Nesbit)

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