Soldiers of the Sudan People Liberation Army celebrate while standing in trenches in Lelo, outside Malakal, South Sudan, on 16 October 2016 Albert Gonzalez Farran/AFP

The top monitor of South Sudan's peace deal has urged the United Nations to hasten the deployment of a regional peacekeeping force to the capital Juba on 24 January.

The United Nations Security Council called for a halt to fighting in South Sudan. UN special envoy on the prevention of genocide, Adama Dieng, earlier expressed fears the nation "could slip into genocide" similar to the one occurred in Rwanda in 1994.

The Joint Monitoring and Evaluation Commission (JMEC), the body in charge with monitoring the implementation of the signed peace agreement, urged the Security Council to speed up the deployment of 4,000 peacekeepers to boost the existing UN force in the conflict-wracked African nation.

JMEC chairman Festus Mogae told the 15-member council that the deployment of the regional protection force in Juba will provide a continued stability in Juba, and enable the government to redeploy army contingents, so far focused on protecting the capital, to the other parts of the country to restore law and order.

"Such spirit of determination, coordinated actions and uniform voices are critical for effective intervention in South Sudan," Mogae, Botswana's former president, said. The former head of state warned the the national dialogue initiative proposed by President Salva Kiir could only bear fruit if its was genuinely inclusive.

South Sudan descended into war in 2013, just two years after gaining independence from Sudan. The conflict erupted when President Kiir, of the Dinka ethnic group, fired his deputy and rebel leader Riek Machar from his cabinet.

Ethnic-related violence targeting Dinka and Nuer ethnic groups then spread, echoing the massacres against Tusti and moderate Hutu that caused at least 800,000 deaths in Rwanda in 1994.

More than three million people have been displaced in the three-year conflict, that has killed tens of thousands, amid allegations of crimes against humanity committed by both sides, including rape, torture and the use of child soldiers.