JUBA, May 3 (Xinhua) -- South Sudanese President Salva Kiir has named a senior military officer facing UN travel ban and asset freeze over alleged violations in the ongoing civil war as new army chief.

In a decree announced on state radio Wednesday evening, Kiir appointed Gabriel Jok Riak as new head of the Sudan People's Liberation Army (SPLA), replacing the late James Ajongo Mawut, who died in Egypt mid April.

In 2015, the UN Security Council sanctioned Riak and two other top SPLA officials over their alleged role in the death of civilians during the start of the civil war in late 2013.

Three top opposition officials were also sanctioned by the UN. South Sudan descended into civil war in late 2013, and the conflict has created one of the fastest growing refugee crises in the world.

The UN estimates that about 4 million South Sudanese have been displaced internally and externally.

A peace deal signed in August 2015 between the rival leaders under United Nations pressure led to the establishment of a transitional unity government, but was shattered by renewed fighting in July 2016.

The next round of peace talks spearheaded by the East African bloc, Intergovernmental Authority on Development (IGAD), is scheduled to reconvene in Ethiopia on May 17.