JUBA: The United Nations said on Sunday it would send more peacekeepers to embattled towns in violence-wracked South Sudan and evacuate “non-critical” staff as fighting raged across the country.

The announcement came as world leaders embarked on a diplomatic push to pull the world’s youngest nation back from the brink of civil war.

Special envoys from the United States and Nigeria were expected in the capital Juba following a mission by foreign ministers from east Africa and the Horn.

The United States meanwhile announced that it had safely evacuated US nationals from the rebel-held city of Bor, a day after an aborted mission in which four US servicemen were injured when their aircraft came under fire in the flashpoint area.

Fighting has gripped South Sudan for a week, after President Salva Kiir accused his former deputy Riek Machar of attempting a coup. Machar has denied this, and has accused Kiir of carrying out a vicious purge of his rivals.

The clashes have left hundreds dead and sent tens of thousands of people fleeing for protection in UN bases or to safer parts of the country, which only won independence from Sudan in 2011, but remains blighted by ethnic divisions, corruption and poverty.The fighting has both ethnic and political dimensions, as troops loyal to Kiir, an ethnic Dinka, battle forces backing Machar, a Nuer.

UN chief Ban Ki-moon called for an immediate end to the violence on Sunday, three days after two Indian peacekeepers were murdered when a UN compound where civilians were sheltering was attacked in the powder-keg state of Jonglei.

According to the UN, some 20 Dinka ethnic civilians were also killed in the assault.

The UN mission in South Sudan (UNMISS) said in a statement it would “reinforce its military presence in Bor and Pariang to continue fulfilling its mandate to help protect South Sudanese civilians”.

Forces loyal to Machar are currently in control of Bor, the capital of Jonglei state and situated about 200 kilometres north of Juba, although South Sudan’s army spokesman said government troops were advancing to retake the town.

Pariang is located in Unity state, the country’s main oil-producing area, which the government has acknowledged is currently in the hands of the rebels.

The UN also said that it had begun evacuating “non-critical” staff from Juba, where nearly 20,000 civilians have taken refuge at UN bases. It did not specify how many employees would be affected by the evacuation order.

“We are not abandoning South Sudan,” stressed the UN Special Representative for South Sudan, Hilde Johnson.

“To anyone who wants to threaten us, attack us or put obstacles in our way, our message remains loud and clear: we will not be intimidated.” Foreign governments, including those of the US, Britain, Uganda, Kenya and Lebanon, have been evacuating their nationals.

US President Barack Obama has warned against a coup attempt in South Sudan, and has sent special envoy Donald Booth to Juba to help foster dialogue.

“Any effort to seize power through the use of military force will result in the end of longstanding support from the United States and the international community,” the White House said.—AFP