U.S. stock index futures were sharply lower on Friday, a day after markets were shut for the U.S. Thanksgiving holiday, as a possible debt default at a Dubai state-owned conglomerate sparked fears of renewed global financial turmoil.

Dubai, part of the oil-exporting United Arab Emirates, said Wednesday it will ask creditors of state-owned Dubai World and builder Nakheel for a standstill agreement on billions of dollars in debt as a first step toward restructuring.

Overseas, Hong Kong shares dropped 4.8 percent while Shanghai stocks fell 2.4 percent on concerns that Dubai would spark a financial relapse.

S&P 500 futures sank 29.8 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 tumbled 222 points, while Nasdaq 100 futures slid 47.25 points.

January crude futures dropped 4.7 percent to $74.28 per barrel Friday, while the U.S. dollar, considered a safe haven for investors, gained 0.7 percent against a basket of currencies <.DXY>.

Investors will get an early pulse on consumer spending for the crucial holiday period with Black Friday, the unofficial start of the holiday shopping season as many stores offer steep discounts. Consumer spending accounts for about 70 percent of the U.S. economy.

No companies are scheduled to report quarterly results on Friday, according to Thomson Reuters data, and no major economic indicators on tap.

Trading volume will likely be low in Friday's shortened session.

In Wednesday trading, stocks rose in light volume as data pointed to stabilization in the labor and housing markets, areas that have fed concerns about a double dip recession.

(Editing by Jeffrey Benkoe)