A statement on Friday by the continental body's Peace and Security Council says the Lord's Resistance Army has not yet been eliminated and could "rejuvenate itself."
The group is led by Joseph Kony, who is wanted by the International Criminal Court for war crimes. He is accused of killing thousands and kidnapping children to become soldiers and sex slaves in Central Africa.
The US military has said the rebel group's active membership is now less than 100, and Uganda's military has said the group has been neutralized. But Kony remains on the run.