ABU Bakr al-Baghdadi, the leader of Isis, has purportedly issued a defiant call for followers to "erupt volcanoes of jihad everywhere".
The 17-minute audio recording, in which he vowed to fight to the last man, was his first public statement since Iraqi officials reported he had been injured in air strikes last week.
In the recording, which appeared to be genuine but has still to be confirmed, the self-appointed "caliph" claimed the group now has bases in Saudi Arabia, Yemen, Egypt, Libya and Algeria.
He specifically called on Isis fighters to launch attacks in Saudi Arabia, particularly on its rulers, and in Yemen. A previous broadcast by al-Baghdadi is thought to have inspired militants in Algeria to kill and behead a Frenchman.
News of the threat comes as the Saudi Arabian leadership landed in Brisbane for the G20 summit.
It remained unclear when the recording was made but in the speech he appeared to refer to the US announcement last Friday that it was to send 1,500 troops to Iraq.
The air strikes that Iraqi officials maintained had left him injured were carried out last Saturday.
There were also reports that al-Baghdadi could have been caught in US air strikes last Friday night. The US said earlier this week that it could not confirm whether he was killed or wounded.
Whether al-Baghdadi is alive or dead, wounded or healthy, the tone of the message was deliberately defiant and incendiary.
Claiming that Isis is expanding rather than being driven back by the "Crusader campaign", he said: "We announce to you the expansion of the Islamic State to new countries, to the countries of the Haramayn, Yemen, Egypt, Libya, Algeria.
"We announce the acceptance of the pledges of allegiance of the brothers who swore loyalty to us in these countries... and the appointment governors."
The speech included a colourful plea for his fighters to bring terror to the world and never to give up: "O soldiers of the Islamic State… erupt volcanoes of jihad everywhere. Light the Earth with fire.
"America and its allies are terrified, weak and powerless. God has ordered us to fight. For that reason the soldiers of the Islamic State are fighting... they will never leave fighting, even if only one soldier remains."
The audio recording was released on social media sites linked to Isis and observers noted that the voice appeared to be the same as a speech confirmed to have been by al-Baghdadi in July, the last time he spoke in public.
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