A new message posted on the internet from what's believed to be the Islamist group ISIL.

In this audio recording, the militant group that's taken over a large swath of Iraq and parts of Syria says it's established a "caliphate" or an Islamic state.

Reuters cannot independently confirm the content of the video but here the flag of ISIL can be clearly identified.

Here militants can be seen literally bulldozing what's believed to be the Syrian-Iraqi border.

The group says its flag flies from Aleppo in northern Syria to Diyala province in eastern Iraq.

In the recording, ISIL says it's renamed itself "the Islamic State", and proclaimed this man Abu Bakr Al-Baghdadi -- seen here in a US department wanted poster -- as its leader.

An alleged spokesperson for the organisation says he'll be known as "Caliph Ibrahim" and that he's also the "leader for Muslims everywhere".

Gulf Arab states, such as Saudi Arabia, are likely to be alarmed by this open declar