Wall Street jittery as ECB action looms

U.S. stock-index futures signaled a softer open on Wednesday as investors face another day of big-name technology and bank earnings, amid speculation that the European Central Bank will announce a new stimulus package Thursday.

Stock futures maintained losses after data showing U.S. housing starts climbed more than expected in December in a hopeful sign for the sluggish housing-market recovery.

UnitedHealth Group rose in early New York trading after posting a better-than-expected fourth-quarter profit; International Business Machines dropped as investors fixated on a less-than-expected forecast for 2015 and Netflix rallied after reporting an adjusted quarterly profit well above estimates.

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A trader works on the floor of the New York Stock Exchange.
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A trader works on the floor of the New York Stock Exchange.

Investors are also on standby ahead of the ECB meeting, with a full-scale bond-buying program considered likely. Analysts expect the ECB Governing Council to agree on a package of at least 500 billion euros (circa 5 percent of GDP). European stocks traded flat to lower ahead of the meeting.

What had looked like a good thing for consumers and their disposable income with the falling price of oil has shifted to hand-wringing amid stories of what crude's drop means for the global economy and capital spending.

Read MoreWall Street debates crude moves

On Wednesday, Crude-oil futures for March delivery rose 79 cents, or 1.7 percent, to $47.26 a barrel on the New York Mercantile Exchange. Gold futures for February gained $6.80, or 0.5 percent, to $1,301.00 an ounce.

The former U.S. Treasury Secretary Larry Summers warned of weakness in the deflation-hit euro zone economy on Tuesday evening, saying that it is on the "brink of deflating" and urgently needs more stimulus, particularly from Germany, Reuters reported.

Read MoreHere's what's haunting the global economy

The first full day of the World Economic Forum in Davos, Switzerland also kicks off Wednesday, where heads of state and government as well as global business leaders are attending, including Chinese Prime Minister Li Keqiang, French President François Hollande and German Chancellor Angela Merkel.

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In the U.K., the Bank of England voted unanimously to keep rates on hold this month for the first time since July last year. Two members of the bank's Monetary Policy Committee that voted for a rate rise in previous months said a hike now could dent the already below-target inflation rate.