IS no longer force it was in 2014: Payne

Two years after declaring its so-called caliphate, Islamic State is no longer the force it was when in 2014, losing half the ground it once held in Iraq and 20 per cent in Syria, the defence minister has told parliament.

Marise Payne said Australian Defence Force members had played a significant role, training some 10,000 members of the Iraqi military and conducting 857 air strikes on Iraq and Syria since October 2014.

"Our efforts have made a very real contribution in the fight to halt the advance of Daesh and to degrade and destroy the terrorist threat," she told the Senate on Monday.