Bemba's army has been trained by Uganda

Mr Ngongi told a news conference in Kinshasa that it was up to Uganda to restore peace in the area, where a power struggle between two Ugandan-backed rebel factions has led to violent ethnic clashes in the past few weeks.

Two weeks ago, troops loyal to Jean Pierre Bemba captured the town of Isiro and the gold mine of Bafwasende - some 350 kilometres west of the Ugandan border - from another rebel group.

Both groups have been armed and trained by the Ugandan army.

Aid problems

The ongoing war in eastern Congo has made it easy for civilians to get access to weapons.

Armed men frequently ambush vehicles, preventing traders and international aid from reaching the town of Bunia.

The UN confirmed that in recent days more than 15,000 civilians have fled fighting and entered Bunia, in search of humanitarian assistance.

On Wednesday, the German agency GTZ managed to bring only two trucks of flour, rice and maize for the displaced in Bunia.

At the end of this month, government representatives and all the rebels are expected to meet for final peace talks in South Africa.

But correspondents say that on the ground rebel leaders are still fighting each other causing devastating damage to civilians and the country's resources, instead of preparing themselves diplomatically.