Iraqi Prime Minister Haider al-Abadi called Monday for a "tribal revolution" against the Islamic State group, in a sign of the importance Baghdad places on tribal resistance against the jihadists.

In a meeting with Suhaib al-Rawi, the newly elected governor of embattled Anbar province, Abadi "stressed the need for a tribal revolution to rid the body of Iraqi society of this foreign enemy", the premier's office said.

He emphasised "the importance of the tribes and the sons of the province taking part in liberating their areas from the terrorist organisations".

IS spearheaded a sweeping militant offensive last year that overran large parts of Iraq, including significant territory in Anbar which stretches from the borders with Syria, Jordan and Saudi Arabia to the western approach to Baghdad.

The support of Iraq's powerful Sunni tribes is seen as essential to defeating IS, and tribal fighters -- who are now being trained by Baghdad -- have played a key role in keeping the jihadists from gaining further ground in Anbar.

Iraqi security forces wilted under the initial IS onslaught last June, but are now backed by US-led air strikes, international advisers, Shiite militiamen and Sunni tribes, and have begun to claw back some areas.