A Ugandan warplane crashed on Wednesday in eastern Democratic Republic of Congo during military operations against Uganda's rebel Lord's Resistance Army, killing the pilot, a local official said.

"A Ugandan fighter crashed" near the airport at Isiro at around 1000 GMT, Medard Autsi, governor of Orientale province, told AFP by telephone.

"I don't know the cause of the accident but it happened during military operations," he said.

Forces from Uganda, Democratic Republic of Congo and south Sudan launched joint action on 14 December against an LRA hideout in northeastern DR Congo, after rebel leader Joseph Kony repeatedly refused to sign a final peace agreement with the Kampala government.

Congo's Foreign Minister Alexis Thambwe Mwamba told journalists in Paris on Tuesday that the operations "are going well," adding, "We believe that in the coming few days, we will be totally rid of Mr Kony's militiamen."

Tens of thousands of people have been killed and nearly two million displaced in two decades of fighting between the Ugandan government and the LRA, which is notorious for abducting children as soldiers and sex slaves.