Ban will brief the 15-nation council behind closed doors on Friday and it will be an "unofficial, interactive dialogue," said Turkish Ambassador Baki Ilkin, whose country presides over the body in June. He provided no other details.         

The meeting takes place in the wake of allegations that 20,000 civilians were killed in the last weeks of fierce fighting between government troops and Liberation Tigers of Tamil Eelam (LTTE) rebels.         

The Sri Lankan government declared victory last month after claiming to have killed LTTE leader Velupillai Prabhakaran. The UN, which has been heavily involved in relief activities during and after the fighting, has said nothing about the killing.         

Amnesty International and other non-governmental organisations called for an official investigation and demanded that the UN make public what it learned about the condition of the civilians before the war ended in Sri Lanka.