ADDIS ABABA (AFP/REUTERS) - South Sudan President Salva Kiir and rebel leader Riek Machar late on Sunday signed a deal to end more than 13 months of fighting in a civil war that has left tens of thousands dead, an AFP reporter saw.

"Complete cessation of hostilities in South Sudan is expected as of this morning (Monday)," Mr Seyoum Mesfin, a negotiator from the regional IGAD bloc, told reporters in the Ethiopian capital Addis Ababa where the ceasefire deal was signed.

The two rivals' agreement is also a power sharing agreement, African diplomatic sources said, where Mr Kiir would remain president in a new administration while Machar would be appointed vice-president, two African diplomats who work for the regional IGAD bloc told Reuters in the Ethiopian capital Addis Ababa.

The two leaders had signed - and then broken - at least six previous ceasefire agreements since fighting began in December 2013.