The U.S. Treasury Department today (Monday) announced it would start selling up to 1.5 billion shares of Citigroup Inc. (NYSE: C ) - a big step in removing government support for bailed out banks. The Treasury owns 7.7 billion shares of Citigroup common stock, giving it 27% ownership of the bank. The sale will leave the government holding just under 22% of shares outstanding, with the rest of the shares being sold later this year. The move brings the government closer to completely exiting the controversial and publicly criticized $700 billion Troubled Asset Relief Program (TARP). " We're putting TARP out of its misery, " Treasury Secretary Timothy F. Geithner said in an interview with CNN .