Warlord Joseph Kony and some of his Lord's Resistance Army commanders are hiding in Sudanese-controlled areas of a disputed enclave in South Sudan bordering the Central African Republic and Sudan, the United Nations said on Tuesday.

In a report to the U.N. Security Council on the activities of Kony's LRA, Secretary-General Ban Ki-moon said Sudan's government had indicated there were no elements of the group in the disputed Kafia Kingi enclave.

"However, credible sources suggest LRA leader Joseph Kony and senior LRA commanders have recently returned to seek safe haven in Sudanese-controlled areas of the enclave," Ban said.

Kony, who has been indicted for war crimes by the International Criminal Court in The Hague, waged a brutal guerrilla war against the Ugandan government in the north of the country for nearly two decades, before fleeing with his fighters into the jungles of central Africa around 2005.