South Sudan's National Assembly and rebels loyal to Riek Machar on Thursday separately ratified the agreement signed last month to end 20 months of fighting in the young country.
Lawmakers voted overwhelmingly at a special parliamentary session in Juba to ratify the deal, which regional bloc IGAD put together over 19 months of stop-and-start talks between the warring sides.
In a seprate vote at the Upper Nile headquarters of Machar's SPLM-in-Opposition (SPLM-IO), leaders of the rebel group also "voted unanimously to ratify and adopt the agreement," SPLM-IO official Ezekiel Lol Gatkuoth said.
The agreement, which Machar signed in Addis Ababa on August 17 and Mr. Kiir signed nine days later in Juba, calls for a ceasefire to take effect within 72 hours of the peace deal being signed by all parties; for a government of national unity to be formed by November, and for a permanent constitution to be drawn up for South Sudan.
The deal also outlines security measures that will be in effect during the transitional period, including the demilitarization of Juba and three other towns.
The government and the armed opposition led by Machar have ordered their forces to lay down arms and respect the ceasefire, which officially took effect late last month.
There are, however, reports of heavy fighting in parts of South Sudan, notably in the main oil-producing state, Upper Nile.
A group that split last month from Machar's rebel movement has told South Sudan in Focus that it is behind the fighting in Upper Nile.
Gathoth Gatkuoth, who until last month as a commander in Machar's SPLM-IO, said the breakaway rebel group is continuing to do battle in Upper Nile because it rejects the leadership of both Mr. Kiir and Machar.