BEIRUT -- The leader of the Islamic State group apparently resurfaced Wednesday, urging his followers to "persevere" and continue fighting the group's enemies everywhere in a purported audio recording, his first in almost a year.

The 54-minute audio entitled "Give Glad Tidings to the Patient" was released by the extremist group's central media arm, al-Furqan Foundation Wednesday evening.

The whereabouts of Abu Bakr al-Baghdadi and the question of whether he is dead or alive have been a continuing source of mystery and confusion. The group has lost around 90 per cent of lands it once controlled in Iraq and Syria where the group declared a caliphate in June 2014.

Al-Baghdadi's last audio message was on Sept. 28, 2017 in which he called on his followers to burn their enemies everywhere and target "media centres of the infidels."

In Wednesday's recording, al-Baghdadi congratulated followers on the occasion of the Muslim al-Ahda feast and made references to current events including Turkey's row with the U.S. over its detention of American pastor Andrew Brunson. If the voice on the audio is confirmed to be that of al-Baghdadi, that would date the message to this month and disprove reports of his death.

Al-Baghdadi said "America is going through the worse time in its entire existence" and said Russia was competing with the U.S. over regional influence and clout.

He also criticizes rebel surrenders in southern Syria to President Bashar Assad's forces, calling them traitors and urges fighters to join the Islamic State group instead.

He urges patience and perseverance and continued jihad.

Al-Baghdadi has only appeared in public once in 2014 in the northern Iraqi city of Mosul. There have been recurring reports of his death or injury, including reports by Russian officials last year who said there was a "high probability" that al-Baghdadi was killed in a Russian airstrike on the outskirts of the Syrian city of Raqqa. U.S. officials later said they believed he was still alive.

Al-Baghdadi's whereabouts are unknown but he is believed to be hiding in the desert that stretches in the Syrian-Iraqi border region.