Al-Qaeda said bin Laden had recorded the message a week before his death [AFP]

Al-Qaeda has released a posthumous audio recording by Osama bin Laden in which the group's late leader praised revolutions sweeping the Arab world.

In the audio posted on Islamist websites on Thursday, bin Laden called on his followers to help efforts to bring down more "tyrants" in the Muslim world.

Bin Laden, who was killed in a US raid on May 2, 2011, in Pakistan, called on al-Qaeda supporters to "set up an operations room that follows up events and works in parallel ... to save the people that are struggling to bring down their tyrants".

Al-Qaeda said bin Laden had recorded the message a week before his death. The audio was included in an Internet video, lasting more than 12 minutes.

In the audio, a voice which appears to be bin Laden's referred to the wave of revolutions which began in the Maghreb region of North Africa.

'Winds of change'

"The sun of the revolution has risen from the Maghreb. The light of the revolution came from Tunisia. It has given the nation tranquility and made the faces of the people happy."

Tunisia's president was overthrown in January, followed by Egyptian leader Hosni Mubarak after mass protests centred on Cairo's Tahrir Square.

"Tunisia was the first but swiftly the knights of Egypt have taken a spark from the free people of Tunisia to Tahrir Square," said bin Laden, adding: "It has made the rulers worried."

He predicted that the winds of change would blow over the entire Muslim world.

"I think that the winds of change will blow over the entire Muslim world, with permission from Allah.

"A delay may cause the opportunity to be lost, and carrying it out before the right time will increase the number of casualties," bin Laden says in the audio message.