In this photo taken Tuesday, Dec. 24, 2013, and released by the United Nations Mission in South Sudan (UNMISS) on Wednesday, Dec. 25, 2013, the U.N.'s top humanitarian official in the country Toby Lanzer, left, makes a visit to assess the humanitarian situation at the U.N. compound where many displaced have sought shelter in Bentiu, in oil-rich Unity state, in South Sudan. (AP Photo/UNMISS, Anna Adhikari)