NAIROBI (Reuters) - Kenya s opposition said on Sunday it had postponed plans to swear in its leader Raila Odinga as an alternative president, easing political tensions and opening a window for possible talks with the government of President Uhuru Kenyatta.  Opposition coalition NASA had planned to publicly  inaugurate  Odinga at a rally on Tuesday, Kenyan independence day, in what the attorney general said this week would be an act of treason.     Kenyatta was re-elected as Kenya s president with 98 percent of the vote in a repeat election held on Oct. 26 which Odinga boycotted. He had beaten Odinga in the original poll, held in August, which was nullified by the Supreme Court on procedural grounds following opposition allegations of vote-rigging and other malpractices.  NASA said in a statement it would postpone the swearing-in after  consultations and engagement with a wide range of national and international interlocutors . It did not specifically name any mediators involved in the talks. The coalition said it would be announcing a new date for the swearing in ceremony and the launch of its People s Assembly  as well as a more vigorous and prolonged resistance . The plan to install Odinga as an alternative president had threatened to exacerbate rifts opened by an acrimonious election season that left more than 70 people dead in political violence.  The United States had also urged opposition leaders to work within the law and avoid actions like the proposed  inauguration ceremony.  