Rebel leader Riek Machar is in Kenya for peace talks.
The South Sudan rebel leader and coup plotter is also to meet his rival President Salva Kiir on Friday where they will talk about peace with President Kenyatta as the middle man.
A cessation of hostilities had been achieved in Ethiopia though keeping it has been marred by intermittent attacks on either side.
Southern Sudan nearly sank into a civil war after Riek Marchar lead a failed coup to overthrow Salva Kiir in Juba.
The failed coup split the military into tribal factions with political leanings.
This has led to a long protracted war which has seen genocide being committed and attacks on United Nations personnel being carried out by the rebels.