Stock index futures dipped on Thursday as global equities tumbled on worries that the lack of a deal on how to handle the Greek debt crisis could trigger disorderly market moves and crimp liquidity.

Investors had their eyes on U.S. weekly jobless claims expected at 8:30 a.m. (1230 GMT). Economists expected claims to fall to 420,000 from 427,000 in the previous week.

Data on housing starts and the Philly Fed business survey were also on tap.

A string of parliamentary resignations threw Greek Prime Minister George Papandreou's plan to reshuffle his cabinet and seek support for a crucial austerity package into disarray. The government risks bankruptcy if it fails to pass a highly unpopular five-year plan.

The European situation has become much more complicated over the last 48 hours, said Paul Mendelsohn, chief investment strategist at Windham Financial Services in Charlotte, Vermont.

He said the risk of a Greek default spiraling into a global liquidity crisis, like the one triggered after the bankruptcy of Lehman Brothers in 2008, depends on Europe's ability to contain the crisis. If it spreads to Portugal, Ireland or Spain, Mendelsohn said, a global recession could return.

World stocks hit a three-month low, the euro tumbled and top-rated government bonds rose as investors began to price in the possibility of a disorderly default in Greek debt.

A day after the S&P 500 fell 1.74 percent, S&P 500 futures dropped 4.1 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 fell 39 points and Nasdaq 100 futures lost 2.5 points.

The S&P 500 closed Wednesday at 1,265.42 and has fallen 7.7 percent from its high in May 2. The benchmark has technical support at 1,256.81, its 200-day moving average, and at the 2011 low near 1,250.

The bulls are going to try to hold these support points, Mendelsohn said. If you were to get a good number in the jobs data, if you get a good housing number, if Philly Fed comes in strong, it might be able to compensate for what's going on in Europe. But that's a lot of ifs.

Housing starts and permits are due at 8:30 a.m. EDT. Economists in a Reuters survey forecast a rise to a 540,000 annualized rate from 523,000 in April, and a total of 558,000 permits in May compared with 563,000 in April.

The Philadelphia Federal Reserve Bank's business activity survey was due at 10 a.m. EDT, with economists expecting a reading of 6.8 versus 3.9 in May.

Research In Motion Ltd will have to struggle to give investors good news when it reports results after markets close on Thursday. Details on when new BlackBerry devices will hit shelves might help.

The CBOE Volatility Index <.VIX> jumped 16.8 percent to 21.32 on Wednesday, its highest since March 18.

(Reporting by Rodrigo Campos; editing by Jeffrey Benkoe)