The New Zealander in the thick of the battle against Islamic State in the Iraqi city of Mosul says their adversary is getting desperate.

Brigadier Hugh McAslan is second in command of the Coalition Land Forces that's making a push to retake the city.

He told Rachel Smalley IS has proved to be a very innovative adversary, making major use of car bombs and drones.

"What they've also done is effectively weaponise that civilian population, and that has included targeting civilians trying to escape, and we've seen a particular uptake in the last two or three weeks as they become a more desperate adversary."

He said they're making gains on the ground, but fighting the ideology of the Islamic State is not something he can deal with.

"The construct of defeating the idea is something that has to be addressed though by Islam and by Muslim nations."

LISTEN ABOVE AS HUGH MCASLAN SPEAKS WITH RACHEL SMALLEY