Non-Arab communities, mainly Kurds, Turkmen and Assyrians make up somewhere between 20% and 25% of Iraq's population. They tend to live in the north of the country. Many of these communities suffered great oppression under Saddam Hussein.

The Kurds are the largest non-Arab community in Iraq by far. The two main Kurdish factions in northern Iraq have a firm base among their own people but would be unlikely contenders for national power.

In an Iraq with a devolved Kurdish region, they would be expected to lead some kind of power-sharing government despite years of often violent rivalry.

Kurds have experienced something of a golden age since the 1991 war in Iraq, protected from Saddam Hussein by a US and UK no-fly zone. What they want now is a real share in central government, along with a form of federal democracy which would protect much of the autonomy they currently have.

During the war in Iraq, Kurdish fighters largely worked under or alongside US forces. Kurdish fighters did go into Kirkuk and Mosul - two strategic northern cities - ahead of US troops. This risked drawing Turkey into the fighting.

Ankara fears Kurdish independence in Iraq might stir up Kurdish nationalism in Turkey.