Stock index futures pointed to a higher open on Wall Street on Wednesday, with futures for the S&P 500 up 0.6 percent, Dow Jones futures up 0.6 percent and Nasdaq 100 futures up 0.4 percent at 4:38 a.m. ET.

European stocks were up 1.3 percent in morning trade, led by buoyant banking shares such as Societe Generale and UniCredit , helped by renewed expectation of a Greek debt deal and after better-than-expected Chinese data.

Amazon.com will be in the spotlight after it warned of a possible first-quarter operating loss following a sharp drop in fourth-quarter profit, a sign the online retailer will keep spending heavily on expansion at the expense of short-term returns. Amazon shares traded in Frankfurt were down 6.9 percent.

On the economic front on Wednesday, investors were awaiting the monthly ADP U.S. national employment report, due at 8:15 a.m. ET, seeking clues as to Friday's key non-farm payroll report. Aside from that, January's U.S. ISM report and December U.S. construction spending data will both be unveiled at 10 a.m. ET.

Facebook was expected to submit paperwork to regulators on Wednesday for a $5 billion initial public offering and has selected Morgan Stanley and four other bookrunners to handle the IPO, sources told IFR.

The U.S. Federal Reserve's pledge to keep interest rates at rock-bottom levels until late 2014 undercut what little confidence Main Street investors had in the markets, Charles Schwab Corp's chief executive said.

Broadcom posted quarterly adjusted earnings that beat Wall Street expectations and its first-quarter revenue forecast reassured investors who sent its shares up 3 percent in after-hours trading.

C.H. Robinson Worldwide , a third-party provider of freight transport, posted a quarterly profit that narrowly missed estimates, hurt by lower margins at its trucking business.

Boston Properties , a real estate investment trust that owns high-end office buildings, posted earnings that nearly doubled when it recorded charges for the early extinguishment of debt and the repurchase of senior notes.

Hard-drive maker Seagate Technology said unit shipments should jump nearly a third this quarter, even though worldwide inventories remain squeezed as its suppliers' factories recover from last year's floods in Thailand.

Suncor Energy , Canada's largest oil and gas producer, said fourth-quarter profit rose 10 percent, helped by higher oil prices.

Mitsubishi UFJ Financial Group <8306.T>, Japan's biggest bank by assets, posted a 39 percent fall in third-quarter net profit, hurt by a tax asset write-down and weak lending at home.

Fortinet posted better-than-expected quarterly results helped by strong sales of its network security products, sending its shares up 8 percent in after-market trading.

Wall Street closed its best month since October on a flat note on Tuesday as weaker-than-expected economic reports surprised investors after a stream of positive data in recent months.

The Dow Jones industrial average <.DJI> dropped 20.81 points, or 0.16 percent, to 12,632.91. The Standard & Poor's 500 Index <.SPX> fell 0.60 points, or 0.05 percent, to 1,312.41. The Nasdaq Composite Index <.IXIC> gained 1.90 points, or 0.07 percent, to 2,813.84.

The S&P 500 triggered a bullish technical signal, known as a golden cross, as its 50-day average ticked above its 200-day average. The signal indicates a shift in mid-term momentum and usually means gains in the index six months down the road.

(Reporting by Blaise Robinson; Editing by Dan Lalor)