South Sudan's warring parties on Monday signed a new ceasefire, but disagreements surfaced about power-sharing, with mediators threatening sanctions against those who blocked attempts to end the eight-month conflict, dpa reported. The ceasefire between President Salva Kiir and rebel leader Riek Machar was brokered by the East African bloc Intergovernmental Authority on Development (IGAD) in Addis Ababa. It foresees the withdrawal of troops and the creation of a 10-kilometre buffer zone. But despite the rebels having accepted the ceasefire, Machar refused to sign a second agreement on the formation of a unity government, threatening to tear up the document in front of the leaders of Ethiopia, Kenya, Djibouti, Uganda, Somalia and Sudan.