As peace talks are set to take place, South Sudan's army says its troops are moving again on the town of Bor in a bid to wrest it back from rebels.
South Sudan's warring parties gathered in Ethiopia on Thursday for talks aimed at ending nearly three weeks of conflict, even as the army said its troops were trying to retake a key rebel-held town.
But as government and rebel negotiating teams gathered at a luxury hotel in Ethiopia's capital Addis Ababa, the army said its troops were moving again on the town of Bor, in a bid to wrest it back from rebels a second time.
"We are ready for talks ... but we will not meet with the government's delegation today," said rebel delegate Yohanis Musa Pouk, amid confusion as to exactly when meetings would start and in what format.
It was not clear if all members of the two delegations had arrived.
"We are participating in talks because we want peace for our people even though the rebel groups have not accepted a cessation of hostilities," the government said in a statement.
Aid workers have increased warnings of a worsening crisis for civilians affected by the still ongoing conflict in South Sudan.
Thousands of people are feared to have been killed in the fighting, pitting army units loyal to President Salva Kiir against a loose alliance of ethnic militia forces and mutinous army commanders nominally headed by ex-vice-president Riek Machar.
Fighting erupted on December 15 when Kiir accused Machar of attempting a coup.
Machar has denied this, in turn accusing the president of conducting a violent purge of his opponents. Fighting has spread across the country, with the rebels seizing several areas in the oil-rich north.
On Tuesday, rebels recaptured Bor, the capital of Jonglei state just 200km north of the capital Juba. The city has changed hands three times since the fighting erupted.
"We are moving on Bor ... leaving the town was part of a tactical retreat, and now we are advancing again," said army spokesperson Philip Aguer.
Civilians in Bor now face "an increasingly dire situation: water, food and medicines are running out, sanitary conditions are worsening", the UN humanitarian chief in the country, Toby Lanzer, said.
Tens of thousands have fled, many paddling in simple boats across the crocodile-inhabited White Nile river to escape the fighting over the town to Awerial in neighbouring lakes.
Lanzer described the situation in Awerial as "critical", with some 75 000 civilians from Bor and elsewhere needing food, water and shelter.
The decision by the two sides to send delegations for initial ceasefire talks has been widely welcomed.
'Reconciliation and healing'
UN special envoy Hilde Johnson said in Juba it was "positive that they are sending delegations", underscoring the dire need for "reconciliation and healing" after the violence.
"We have seen terrible acts of violence in the past two weeks… and as we know, if there is no one held accountable, there is a major risk that the violence can continue," she added.
Over 200 000 Sudanese refugees who had fled the fighting face a grim situation, with many aid workers who had been supporting them evacuated.
Close to 200 000 civilians have been forced to flee their homes, including some 57 000 seeking refuge with badly overstretched UN peacekeepers.
The conflict has also been marked by an upsurge of ethnic violence pitting members of Kiir's Dinka ethnic group against Machar's Nuer community, and the UN Mission in South Sudan (UNMISS) said that "atrocities are continuing to occur" across the country.
UNMISS reported "extra-judicial killings of civilians and captured soldiers" and the "discovery of large numbers of bodies" in Juba, Bor and Malakal, the main town in oil-producing Upper Nile state.
On Tuesday, Machar told Agence France-Presse via satellite phone that he was not yet ready to agree to an immediate ceasefire nor hold face-to-face talks with Kiir.
South Sudan's independence
"There is no cessation of hostilities yet," Machar said. "That is what the delegation going to Addis Ababa is going to discuss."
Kiir has described the war as "senseless", but has ruled out power sharing with the rebels.
"If you want power, you don't rebel so that you are awarded with the power," Kiir said in an interview broadcast on the BBC.
South Sudan won independence from Sudan in 2011 after decades of civil war. – Sapa-AFP