U.S. President Barack Obama (R) meets with his national security staff to discuss the situation in Syria in the Situation Room of the White House in Washington, in this file handout photo taken August... more 
U.S. President Barack Obama (R) meets with his national security staff to discuss the situation in Syria in the Situation Room of the White House in Washington, in this file handout photo taken August 30, 2013, courtesy of the White House. A report by U.N. chemical weapons experts will likely confirm that poison gas was used in an August 21 attack on Damascus suburbs that killed hundreds of people, U.N. Secretary-General Ban Ki-moon said on September 13, 2013. France's U.N. ambassador, Gerard Araud, told reporters that September 16, 2013 is the tentative date for Ban to present Sellstrom's report to the Security Council and other U.N. member states. REUTERS/Pete Souza/White House/Handout via Reuters/Files (UNITED STATES - Tags: POLITICS CONFLICT) ATTENTION EDITORS - THIS IMAGE WAS PROVIDED BY A THIRD PARTY. FOR EDITORIAL USE ONLY. NOT FOR SALE FOR MARKETING OR ADVERTISING CAMPAIGNS. THIS PICTURE IS DISTRIBUTED EXACTLY AS RECEIVED BY REUTERS, AS A SERVICE TO CLIENTS less 
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Reuters | Photo By HANDOUT / REUTERS
Mon, Sep 16, 2013 3:42 AM EDT