FILE PHOTO: US Deputy Secretary of State Burns makes remarks at the start of the Ecopartnership event of the U.S.-China S&ED in Washington

FILE PHOTO: U.S. Deputy Secretary of State William Burns makes remarks at the start of the Ecopartnership event of the U.S.-China Strategic and Economic Dialogue (S&ED) at the State Department in Washington July 11, 2013. REUTERS/Jonathan Ernst/File Photo