Defence chief Angus Houston has ruled out using tanks in Afghanistan.
The opposition's defence spokesman David Johnston has called for tanks to be sent to Afghanistan.
It was a major plank in Senator Johnston's call for more resources for the war effort - a call that was broadly shot down by the government and defence experts.
Few nations have tanks in the central Asian nation because of its largely mountainous terrain.
Air Chief Marshal Houston told a Senate estimates hearing on Tuesday that "heavy armoured vehicles" were not suited to the Australian task in the terrain ....