Stock index futures pointed to a mixed open on Wall Street on Tuesday as U.S. markets reopen after a long holiday weekend, with futures for the S&P 500 down 0.04 percent, Dow Jones futures down 0.07 percent and Nasdaq 100 futures up 0.2 percent at 1030 GMT (5:30 a.m. EST).

All eyes were on Citigroup , due to report quarterly results before the bell. Earnings from IBM were also expected on Tuesday.

On the M&A front, Kraft Foods agreed a recommended deal to buy Cadbury for around $19.6 billion, creating the world's top confectioner after frantic last-minute talks broke an impasse over price.

Shares in Kraft Foods in Frankfurt rose 0.2 percent.

Industrial conglomerate Tyco International will acquire Broadview Security for $1.9 billion in a deal that brings together two large providers of residential and commercial security in North America, the two companies said on Monday.

Airlines will be in the spotlight after Japan Airlines Corp <9205.T> filed for bankruptcy protection, owing more than $25 billion and vowed to slash 15,700 jobs and unprofitable routes as part of a plan to survive an industry beset by volatile fuel costs and fickle flyers.

Apple Inc will host a special event on January 27 where it is widely expected to unveil its tablet computer, as the company looks to extend its hot hand into a brand new product category.

Goodyear Tire & Rubber Co on Monday said it expects to record a charge of about $150 million in the first quarter due to Venezuela's devaluation of its currency earlier this month.

Foreign firms, including Google , must respect Chinese laws and customs, China's foreign ministry spokesman said on Tuesday, a week after the world's largest search engine said it might pull out of China due to hacking and censorship.

Oil prices were steady above $78 a barrel on Tuesday on expectations that Chinese economic indicators to be published this week will signal strong demand growth from the world's second-largest oil consumer.

Japan's Nikkei share average fell 0.8 percent on Tuesday, with exporters such as Honda Motor Co <7267.T> hurt by a stronger yen, while European stocks dropped 0.6 percent in morning trade, with banks featuring among the top losers.

On Friday, U.S. stocks slid after JPMorgan Chase & Co reported deep fourth-quarter loan losses and raised concerns about bank profits, while a weaker-than-expected Reuters/University of Michigan Surveys of Consumers for early January also hurt shares, as consumer worries about incomes and unemployment rose.

The Dow Jones industrial average <.DJI> dropped 100.90 points, or 0.94 percent, to 10,609.65. The Standard & Poor's 500 Index <.SPX> fell 12.43 points, or 1.08 percent, to 1,136.03. The Nasdaq Composite Index <.IXIC> lost 28.75 points, or 1.24 percent, to 2,287.99.

(Reporting by Blaise Robinson; Editing by Mike Nesbit)