The leader of Boko Haram, Abubakar Shekau, said he is alive and still head of the Nigeria-based jihadist group, according to a new audio recording released on Sunday.

Shekau said in the eight-minute Hausa-language recording that global media reported "that I am dead or that I am sick and incapacitated and have lost influence in the affairs of religion".

"It should be understood that this is false. This is indeed a lie. If it were true, my voice wouldn't have been heard, now that I am speaking," he said, denying previous claims by the Nigerian military that he had been killed.