The UN Security Council will hold a closed door meeting today on renewed fighting in the capital of South Sudan, diplomats said.
Secretary General Ban Ki-moon said he was "shocked and appalled" by the fighting between government and former rebel forces in the capital Juba and called on both sides to halt the violence.
South Sudan has seen more fighting than peace since winning independence from Sudan in July 2011.
Civil war broke out in December 2013 when President Salva Kiir accused his vice president Riek Machar of plotting a coup.
An August 2015 peace deal was supposed to end the conflict. But the peace process has stalled while fighting has continued despite the establishment of a unity government.
Machar went from being vice president to rebel leader and then back to vice president under the unity government.
