NEW YORK ( TheStreet) -- U.S. stock futures were suggesting a flat open for Wall Street on Thursday as U.S. lawmakers trying to reach an agreement on how to avert the so-called fiscal cliff appeared at an impasse. European shares were lower while Asian stocks ended Thursday's session mixed. Japan's Nikkei 225 index fell 1.2% to close at 10,039.33. The White House on Wednesday threatened to veto House Speaker John Boehner's alternative tax plan as the Jan. 1 fiscal-cliff deadline nears. Boehner has said Republicans in the House may vote Thursday on his "Plan B" bill. The economic calendar in the U.S. Thursday includes the third and final estimate gross domestic product estimate from the Commerce Department at 8.30 a.m. EST, and the Labor Department's weekly jobless claims report, also at 8:30 a.m. U.S. stocks on Wednesday fell for the first time this week as politicians wrangled over the "fiscal cliff" deal in Washington. The Dow Jones Industrial Average declined 99 points, or 0.74%, to 13,252 on Wednesday. NYSE Euronext ( NYX), the operator of the New York Stock Exchange, is in talks to sell itself to rival IntercontinentalExchange ( ICE), according to reports. People close to the discussions told The Wall Street Journal an announcement could come as early as Thursday. Under a deal, ICE would value NYSE at $33 a share, a 37% premium to its closing price on Wednesday, according to a report from CNBC. Research In Motion ( RIMM), the BlackBerry maker, is expected by analysts on Thursday to post a fiscal third-quarter loss of 35 cents a share. RIM, which has steadily been losing market share in the U.S., is banking on reversing its fortunes with BlackBerry 10, the new operating system that will be unveiled at the end of next month. Earnings are also being reported Thursday from the likes of ConAgra Foods ( CAG), Nike ( NKE) and Discover Financial Services ( DFS). An experimental therapy from Amicus Therapeutics ( FOLD) and GlaxoSmithKline ( GSK) failed to improve kidney response in Fabry disease patients compared to placebo in a late-stage study, the companies disclosed late Wednesday. Bed Bath & Beyond ( BBBY) on Wednesday issued forecasts for the fourth quarter and fiscal year that were below analysts' views. Stephen Gillett, president of Best Buy's ( BBY) digital business, is joining Symantec ( SYMC) as chief operating officer. -- Written by Joseph Woelfel >To contact the writer of this article, click here: Joseph Woelfel >To submit a news tip, send an email to: email@example.com.