FILE - In this April 24, 2014, file photo provided by the United Nations Relief and Works Agency for Palestine Refugees in the Near East (UNRWA), residents of the besieged Palestinian camp of Yarmouk stand in line to receive aid food distributed by UNRWA on the southern edge of the Syrian capital, Damascus. Conditions in the camp have deteriorated since Islamic State militants muscled their way into it in early April 2015. The militants are trying to consolidate their hold on the camp. (AP Photo/UNRWA, File)
FILE -- In this Jan. 31, 2014, file photo, released by the United Nations Relief and Works Agency for Palestine Refugees in the Near East (UNRWA), shows residents of the besieged Palestinian camp of Yarmouk, queuing to receive food supplies, in Damascus, Syria. In one besieged neighborhood after another, weary rebels have turned over their weapons to the Syrian government in exchange for an easing of suffocating blockades that have prevented food, medicine and other staples from reaching civilians trapped inside. The government touts the truces as part of its program of “national reconciliation” to end Syria’s crisis, which has killed more than 140,000 people since March 2011. (AP Photo/UNRWA, File)
AP10ThingsToSee - This Jan. 31, 2014 photo released by the United Nations Relief and Works Agency for Palestine Refugees in the Near East (UNRWA, residents of the besieged Palestinian camp of Yarmouk line up to receive food supplies, in Damascus, Syria. A United Nations official is calling on warring sides in Syria to allow aid workers to resume distribution of food and medicine in a besieged Palestinian district of Damascus. (AP Photo/UNRWA, File)