South Sudan rebels, army trade blame for fresh fighting

South Sudan's army and rebels accused each other of sparking fresh fighting on Saturday in the north-east, hours before the start of a ceasefire to end a brutal 20-month civil war.

The warring sides traded blame for breaching the terms of a peace deal, brokered by the regional eight-nation IGAD bloc along with the United Nations, the African Union, China, Britain, Norway and the United States.

"Riek Machar's rebels attacked Malakal yesterday (Friday)", and the "assault on Malakal resumed this (Saturday) morning," army spokesman Colonel Philip Aguer told a press conference.

"We want the IGAD to establish the presence of a ceasefire mechanism in all the counties," Aguer said.

"That's untrue, their forces attacked us near Malakal," rebel spokesman James Gatdet Dak told AFP, referring to a strategic northeastern town and a gateway to the country's last remaining major oil fields.

"They wanted to seize the area before the ceasefire comes into effect," he said.

It was not immediately clear if the ceasefire had entered into force on Saturday afternoon in the world's newest nation which broke away from Sudan four years ago. Dak said it was supposed to come into effect at midnight (2100 GMT Saturday).

Information minister and government spokesman Michael Makuei said: "This is of course a violation of the cessation of hostilities of the agreement and it should be recorded."

The rebels repeated the accusation and called for the government to be severely condemned.

"We suspect that their plan is to launch a full-scale offensive against our bases around Malakal. This is a serious violation of the terms of the peace agreement," a rebel statement said.

But IGAD spokesman Hailemichael Gebreselassie disclaimed any knowledge of the clashes, saying: "We haven't heard anything related to any incidents."

The accord, signed by rebel leader Machar on August 17 and the government only on Wednesday, gave a 72-hour deadline for a permanent cessation of hostilities.

Aguer said the rebels attacked Malakal, the state capital of Upper Nile, overnight "using mortars and machineguns" and resumed shelling on Saturday.

He said one government soldier was wounded, adding: "Though the army is committed to the spirit of peace and welcome the internationally supported peace initiative, (it has) all the rights for self defence and for protection of Malakal town and the surrounding areas."

- Peace deal a 'humiliation' -

South Sudan's civil war began in December 2013 when President Salva Kiir accused his former deputy Riek Machar of planning a coup, setting off a cycle of retaliatory killings across the country that has split the poverty-stricken, landlocked country along ethnic lines.

Facing the threat of international sanctions, Kiir finally signed the deal this week but annexed a list of reservations that he said would have to be addressed for the deal to take hold.

Machar, for his part, has said the reservations cast "doubts" on the government's commitment.

The UN Security Council on Friday called for the ceasefire to begin immediately and threatened sanctions against those who undermine the accord.

Two powerful rebel generals, Peter Gadet and Gathoth Gatkuoth, split from Machar earlier this month, accusing him of seeking power for himself.

The government has said the split is a key reason they doubt the peace deal can be effective.

The signed deal gives the rebels the post of first vice president, which means that Machar would likely return to the job he was sacked from, an event which put the country on the path to war later that year.

But the 12-page government list of reservations on the peace deal calls this a "humiliation" and a "reward for rebellion", and insists the post of first vice-president must be on equal footing with the current vice-president, whose post remains.

At least seven ceasefires have already been agreed and then shattered within days or even hours.

Over two million people have fled their homes from a war marked by ethnic killings, gang rapes and child soldier recruitment. Some 200,000 terrified civilians are sheltering inside UN bases.