Osama bin Laden has scolded his Al-Qaida followers in Iraq and other insurgents, saying they have "been lax" for failing to overcome fanatical tribal loyalties and unite in the fight against US troops.

The message of his new audiotape reflected the growing disarray among Iraq's Sunni Arab insurgents and bin Laden's client group in the country, both of which are facing heavy US military pressure and an uprising among Sunni tribesmen.

In the brief tape played on Monday on Al-Jazeera television, the terrorist leader urged militants to "beware of division ... The Muslim world is waiting for you to gather under one banner".