Representatives from the South Sudanese government and a rebel force fighting to overthrow it have opened peace talks in Ethiopia.
Regional mediators hope to broker a cease-fire to end three weeks of conflict that has pushed the world's newest country toward civil war.
Ethiopia's Foreign Ministry says the talks began Friday, adding the East African regional bloc IGAD (Intergovernmental Authority on Development) is committed to help in any way possible.
Fighting between the forces of President Salva Kiir and ex-vice president Riek Machar has left more than 1,000 people dead.
Both sides continue to fight as the talks began. Government troops are said to be moving in on Bor, the rebel-held Jonglei state capital, nearly 200 kilometers north of Juba. However, rebel commanders have warned they are preparing to advance from Bor to Juba.
The U.S. embassy in Juba has ordered the evacuation of more staff due to the "deteriorating security situation."
An embassy statement urged all U.S. citizens to leave, saying there will be a State Department-arranged evacuation flight on Friday.
In a later statement, the U.S. State Department said the U.S. "remains deeply and actively committed to supporting regional and international efforts to end the violence."
Toward that goal, the U.S. announced nearly $50 million in new humanitarian assistance. The U.S. has now given more than $300 million toward humanitarian efforts in South Sudan.
The United Nations refugee agency said Thursday more than 200,000 people have been internally displaced since violence erupted in mid-December.
U.N. spokesman Daniel MacIsaac also tells VOA that more than 10,000 South Sudanese have fled to neighboring countries.
The violence began when renegade soldiers attacked a South Sudanese army headquarters on December 15. President Kiir accused former vice president Machar of a coup attempt.
Machar told VOA Wednesday that President Kiir is responsible for much of the unrest. He said peace cannot be achieved under the president's leadership.
Mr. Kiir declared a state of emergency Wednesday in Jonglei state, as well as the oil-producing Unity state, which has been one of the other main sites of the fighting.
Witnesses say some of the violence is ethnically motivated, with supporters of Mr. Kiir, a member of the Dinka tribe, and supporters of Machar, from the Nuer tribe, targeting each other.