Sudanese tensions

The Sudanese government has threatened retaliation against South Sudan after accusing its neighbor of backing a rebel incursion against a government military base in Sudanese territory around the Jau border region.

Sudan said 1,500 rebels, accompanied by officers from South Sudan's army, launched a "direct attack" on the base which is just a few kilometers inside the border.

Sudan said it would lodge a complaint with the United Nations Security Council.

Insurgents said in a statement that they killed 150 Sudanese soldiers in Sunday's attack, a claim rejected by the Sudanese government who said their forces had killed "a huge number" of rebels, but gave no concrete figures.

This is the first attack by a new alliance of insurgents from the Sudan People's Liberation Movement-North (SPLM-N) and the Justice and Equality Movement (JEM) who formed a revolutionary front last year. The alliance aims to topple the Khartoum regime.

The fighting comes less than three weeks after the two neighbors signed a non-aggression pact.

Rebel force 'just a pawn'

South Sudan denied that it has been supporting rebel groups to fight Sudan, and insisted that its soldiers "have not crossed (the) border" because Jau belonged to South Sudan, not to Sudan.

Magdi El Gizouli, an analyst at the Sudanese Rift Valley Institute, said the attack could not have occurred without direct involvement by South Sudan's army.

The fighting should be seen as part of the "bargaining process" between Sudan and its southern neighbor who are at loggerheads over oil transit fees, El Gizouli said.

"I think the rebel force is now just a pawn in a bigger process," he told AFP.

Never-ending oil negotiations

This latest spat comes as Sudan asked China, the biggest investor in oil facilities in both countries, to help resolve the ongoing oil dispute.  

In January, the South Sudanese government stopped piping its oil to a Sudanese port on the Red Sea after accusing the Khartoum government of stealing oil.

Landlocked South Sudan has limited alternatives to ship the 350,000 barrels of oil it produces daily. The two sides are at loggerheads over how much South Sudan should pay for its oil transit.

On Tuesday, Sudan accused its southern neighbor of stonewalling over the dispute. Sudan Foreign Minister Ali Ahmed Karti denied "confiscating" the oil, saying the South had used Sudan's facilities, equipment and ports without "paying a penny."

Without oil sales, which bring in 98 percent of South Sudan's revenue, the economic situation is worsening in the new nation, which has almost no other alternative sources of income.