Futures Up Slightly Ahead of Open

U.S. stock index futures rose ahead of the open Monday, but trading was light at the beginning of the week before Christmas.

Thin trading volumes, geopolitical tensions in Korea and euro zone debt concerns could bring volatility to the markets the days ahead, as the market attempts to hold on to strong December gains. Through last Friday,the Dow was up nearly 4.5 percent, and the S&P 500 Index was up more than 5 percent.

"There's a lot of volatility on very small amounts of volume so I don't believe that people should be shifting their views of the world based on a few thin days trading as you lead up to Christmas," Julian Pendock, partner at Senhouse Capital, told CNBC.

European shares were making modest gains, with automobile and utility companies seeing strength. Nervousness surrounding the region's debt situation remained, with the European Central Bank expressing "serious concerns" because of the Irish bailout. Meanwhile, the ECB's Jean-Claude Trichet said countries must do more to individually tackle the crisis.

The euro came under pressure on the back of the concerns with the Swiss franc hitting an all-time high versus the single currency.

Airline stocks, such as British Airways and Air France, were down as many Western European airports were all but closed by snow and freezing cold weather.

Asian stocks closed mostly lower as tensions between North and South Korea re-emerged following live firing drills carried out by South Korea in a disputed area. North Korea, however, said it would not respond to the "reckless" military drills.

In corporate news, AT&T shares rose slightly after news the telecom giant plans to buy acquire wireless spectrum licenses from Qualcomm for $1.9 billion to boost its high-speed, next-generation "4G" network. Qualcomm's shares also gained.

Sara Lee slipped after news over the weekend that the food maker has been talking about selling itself to Brazilian meat producer JBS, but that the companies haven't been able to reach an agreement.

In corporate news, Sony said it expected to miss its sales target of 25 million LCD TVs for the year to March 2011 Sunday.

Raytheon plans to acquired Applied Signal Technology , a move that will allow the defense contractor to expand its intelligence products. Applied Signal makes communication interception gear.

On the earnings front, Jefferies Group gained in pre-market trading after reporting better-than-expected earnings in the fiscal fourth quarter, and declaring a quarterly dividend of $0.075 a share.

Adobe Systems and Darden Restaurants will report numbers after the closing bell.

And the Senate is set to vote Tuesday on the government spending bill. Senate Majority Leader Harry Reid said a compromise had been reached among Senate leaders ahead of the vote.

On the Calendar This Week:

MONDAY: Earnings Adobe Systems.
TUESDAY: FCC votes on net neutrality; earnings from ConAgra and Nike.
WEDNESDAY: MBA mortgage applications, GDP, existing home sales, oil inventories; before-the-ell earnings from Walgreen; after-the-bell earnings from Bed, Bath & Beyond.
THURSDAY: NYSE early close; durable goods orders, personal income and spending, weekly jobless claims, consumer sentiment, new home sales.
FRIDAY: Markets closed for Christmas.

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