Shelling in South Sudan oil town

Rebel fighters in South Sudan bombarded government positions Tuesday in the oil town of Bentiu, a day after the UN launched a $1.8 billion aid appeal to stave off famine in the war-wracked country.

Loud explosions were heard in the northern town, capital of Unity state and one of the hardest fought over regions in the 14-month long war, and where 53,000 civilians are sheltering inside a United Nations camp.

"The rebels are shelling our positions in Bentiu," Defence Minister Kuol Manyang told AFP. "This is a violation of the cessation of hostilities agreement, and we will act in self defence."

A South Sudanese People's Liberation Army national army soldier walks past displaced people in the town of Bentiu, on January 12, 2014

A South Sudanese People's Liberation Army national army soldier walks past displaced people in the town of Bentiu, on January 12, 2014 ©Simon Maina (AFP/File)

Aid workers in the northern town of Bentiu confirmed the shelling, saying they briefly took shelter in bunkers.

Fighting broke out in South Sudan, the world's youngest nation, in December 2013 when President Kiir accused his sacked deputy Riek Machar of attempting a coup.

The fighting in the capital Juba set off a cycle of retaliatory massacres across the country. Both government forces loyal to Kiir and rebels loyal to Machar continue to fight, despite numerous ceasefire deals.

The UN estimates that 2.5 million people are in a state of emergency or crisis, steps just short of famine.

- 'Man-made crisis' -

The latest fighting comes a day after donors pledged $529 million (467 million euros) towards a $1.8 billion aid appeal by the UN, with over 2.5 million people on the brink of famine.

UN aid chief Valerie Amos on Monday warned the warring leaders they had to show a committment to peace.

Top US official Anne C. Richard said that no conflict around the world today filled Washington with as "much frustration and despair" as South Sudan.

Richard, US Assistant Secretary of State for Refugees, said some areas were "teetering on the brink of famine", and that people "continue to suffer and die unnecessarily because their leaders are unwilling to do what it takes to restore peace."

Kiir and rebel leader Riek Machar have been set a March 5 deadline to strike a final peace agreement, but previous deadlines have been repeatedly ignored despite the threat of sanctions.

The next round of faltering peace talks is due to resume on February 19.

Washington, a key backer of South Sudan's independence in 2011, warned the leaders on Tuesday they "bear full responsibility for this man-made crisis" and must make "the needed compromises to reach a final agreement."

Almost two million have been forced from their homes and 500,000 of them have fled abroad to neighbouring countries.

No overall death toll for the war has been kept by the government, rebels or the United Nations, but the International Crisis Group says it estimates that at least 50,000 people have been killed.

Fighting in South Sudan has forced almost two million people from their homes and 500,000 of them have fled abroad

Fighting in South Sudan has forced almost two million people from their homes and 500,000 of them have fled abroad ©Phil Moore (AFP/File)

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