Both President Salva Kiir and Dr Riek Machar are former rebel leaders who rose to power during Sudan's 1983-2005 civil war between north and south.
The signing ceremony is expected to be attended by the IGAD leaders
The rival groups have already agreed on a permanent ceasefire and withdrawing of their forces from civilian areas.
The latest agreement is part of renewed regional diplomatic efforts to end a conflict that has killed tens of thousands of people.
“The ad hoc committee exchanged views on how to more effectively enhance its support to and co-operation with IGAD in the ongoing efforts to resolve the...
"This day was expected by our people in South Sudan and it has now come," Kiir says after the signing of the agreement.
The latest push for peace in South Sudan launched by regional leaders last week in Addis Ababa comes as the two warring factions face a looming deadline...
A preparatory team from the Intergovernmental Authority on Development (IGAD), the East African bloc under whose auspices the talks are being held, is...
Oil production, from which South Sudan gained 98% of its revenues on its independence, has plummeted to about 120,000 barrels a day.
But analysts say the outcome remains unclear given President Kiir and rebel leader Machar's notoriously volatile relationship.
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