An estimated 400 civilians have been killed in the region and more than 83,000 people have fled their homes since 1 January because to the violence, according to UN Office for the Co-ordination of Humanitarian Affairs.

"Reports of civilians being killed, wounded or displaced have become a daily occurrence,” it said.

The violence has forced aid agencies to either delay, suspend or relocate operations.

The UN said 1.9 million people were displaced within Ituri and some three million others were severely food insecure.

Many armed groups operate in conflict-torn Ituri and neighbouring North Kivu province, where martial law in place since last May has failed to end bloodshed.