Australian forces are playing a key role in the escalating battle for the Iraqi city of Mosul, bombing 130 Islamic State targets and deploying special forces medics close to the frontline to treat wounded Iraqi soldiers.

RAAF pilots have hit IS fighters, car bomb factories, artillery positions, weapons caches, tunnel entrances and water supplies across the city since October, when Iraq and its coalition supporters launched their offensive.

With the fighting now set to enter a deadly new phase as the Iraqi forces start pushing into the perilous IS stronghold of West Mosul, Australian medics near the battlefield are preparing for a sharp increase in casualties.

Mosul fell to IS militants in 2014, the largest city to come under extremist control. Iraq hopes to reclaim it in the coming months, but the fight will require intense, street-to-street fighting in heavily populated areas.