US President Barack Obama has decided to nominate his Chief-of-Staff Jack Lew as his next Treasury Secretary to replace Timothy Geithner. Media reports said, an announcement in this regard is likely to me made today. Lew, who previously served as Director of the Office ofManagement and Budget in the Clinton and Obama Administration, is a member of the Democratic Party. Treasury Secretary Timothy Geithner has said that he would like to leave the post by the end of the month.