Regional efforts to broker a peace deal in violence-ridden South Sudan have picked up, with the leaders of Kenya and Ethiopia arriving for talks in Juba.
Kenyan President Uhuru Kenyatta and Ethiopian Prime Minister Hailemariam Desalegn will meet South Sudanese President Salva Kiir in the capital later Thursday.
Kiir accuses his ex-deputy and political rival, Riek Machar, of masterminding a coup attempt that sparked fierce clashes 11 days ago.
U.N. officials say it is likely thousands have been killed in the violence, which has pitted Kiir's Dinka ethnic group against the Nuer ethnic group of Machar.
Machar, who is on the run, has denied making a coup attempt. However, since the violence started he has called on the army to remove Kiir from power.
Meanwhile, more than 40,000 people remain sheltered at U.N. bases, seeking refuge from the fighting.
The latest fighting is centered in Malakal, capital of oil-rich Upper Nile State, between rebels and government loyalists. Earlier this week, government troops retook the key town of Bor in Jonglei state from rebel forces.
U.N. Secretary-General Ban Ki-moon has called on the country's leaders to settle their differences peacefully, and protect civilians from attacks.
On Tuesday, the U.N. Security Council voted to send an additional 5,500 peacekeepers to South Sudan.
Earlier, U.S. Secretary of State John Kerry called both President Kiir and former vice president Machar, urging them to halt the fighting and hold mediated political talks.
Both men have said they are ready for dialogue, but the government rejected Machar's demand that detained opposition leaders be released first.