Stock index futures edged higher on Wednesday, following two days of sharp market losses, with developments in Greece and a U.S. monetary policy meeting in focus.

French and German leaders will aim to push for quick implementation of the Greek bailout deal after the Athens government unsettled global financial markets by calling for a referendum on the plan. Greek Prime Minister George Papandreou won the backing of his cabinet to hold the referendum.

Papandreou's move triggered a slide in global stocks. The U.S. benchmark S&P 500 index fell 5.2 percent over the past two sessions, even as it closed its best month in 20 years on Monday.

After two horrific days we try to get some clarity on the Greek referendum and we hear from (Federal Reserve Chairman Ben) Bernanke. All of that plays out in a short-term oversold market to a bit of a bounce at the open, said Art Hogan, managing director of Lazard Capital Markets in New York.

The Fed looked set to take a breather from monetary stimulus measures on Wednesday, even if financial market turbulence heightens the chances of action later. Bernanke will hold a media briefing at 2:15 p.m. EDT (1815 GMT).

S&P 500 futures rose 4.8 points and were above 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 gained 25 points, and Nasdaq 100 futures added 5.5 points.

ADP releases its October employment report at 8:15 a.m. EDT (1215 GMT). Economists in a Reuters survey expected that 101,000 jobs were created in October versus 91,000 in September.

On the earnings front, Comcast Corp posted a stronger quarterly profit as its traditional cable business offset weaker results from two newer media properties, the NBC television network and Universal Pictures. Revenues rose 5 percent.

Also due to report results are Kraft Foods Inc, MasterCard Inc, and News Corp.

(Reporting by Rodrigo Campos; editing by Jeffrey Benkoe)