Photo taken on Oct. 16, 2016 shows South Sudan's government troops on a military truck preparing a journey to the frontline in Malakal, South Sudan.(Xinhua/Gale Julius)

ADDIS ABABA, Dec. 22 (Xinhua) -- South Sudan's government and rebel groups have signed a new agreement here in a bid to end a four-year civil war.

The agreement was inked on Thursday following the peace talks in the Revitalization Forum for the Agreement on the Resolution of the Conflict in South Sudan, led by a regional bloc the Intergovernmental Authority on Development since Dec. 17 in Ethiopia's capital Addis Ababa.

During the opening of the Forum, the African Union said that the week would mark the beginning of a genuine reconciliation and the end of the nightmare that the people of South Sudan have been living through since December 2013.

The pan-African bloc welcomed the new deal later, and stressed the need of the full and effective implementation of the agreement to end violence and uphold the most basic tenets of international humanitarian law.

South Sudan descended into violence after the political dispute between President Salva Kiir and his former deputy turned rebel chief Riek Machar led to split the army, leaving soldiers to fight alongside ethnic lines.

A 2015 peace agreement aimed at ending the conflict was weakened after the outbreak of renewed fighting in July 2016 forced the opposition rebel leader Machar to flee the South Sudanese capital of Juba.