Negotiators from South Sudan’s two warring sides arrived in Ethiopia on Wednesday for peace talks, and a U.N. official urged both teams to bring the world’s newest country “back from the brink.”

A government official said fighting continued in Bor, a gateway city to the capital, Juba. Bor, the capital of Jonglei state and just 75 miles from Juba, is the center of ethnically based violence stemming from the political rivalry ­between President Salva Kiir and ousted vice president Riek Machar, the rebel leader accused of mounting a coup attempt.

The fighting has left more than 1,000 people dead, the United Nations says.

Kiir declared a state of emergency Wednesday in Jonglei and Unity, two states where rebel forces have gained the upper hand in recent fighting.

Machar said Tuesday that he would send his forces from Bor to Juba, but Hilde Johnson, the U.N. representative in South Sudan, played down the threat.

“I think we need to take quotations with pinches of salt at this point of time,” she said. “On January 1 the country is at a fork in the road, but it can still be saved from further major escalation of violence.”

Johnson urged Kiir and Machar to use the talks to move toward peace, adding: “They can still pull the country back from the brink.”

Pro-Machar forces in Bor seem to be taking defensive positions, Johnson said. The fighting in Bor has displaced about 60,000 people. The International Committee of the Red Cross said the road from Bor to the nearby Awerial area was lined with people waiting for boats so they could cross the Nile River.

Two teams of five negotiators each arrived in Addis Ababa, ­Ethiopia, and were expected to begin talks later Wednesday, said Getachew Reda, a spokesman for Ethiopia’s prime minister.

The United Nations said Tuesday that it is “gravely concerned” about mounting evidence of gross violations of international human rights law, including extrajudicial killings of civilians and captured soldiers.

South Sudanese Foreign Minister Barnaba Marial Benjamin labeled Bor a war zone, and one analyst said government troops had pulled out of parts of the city because they were concerned about having to kill the “young boys” who fill the rebel ranks.

The military “was told to withdraw,” said Edmund Yakani, executive director of the Juba-based group Community Empowerment for Progress, citing accounts of contacts in Bor. “They communicated that these are young boys and we are killing them like nothing.”

— Associated Press