The Australian Government is hinting that it may be able to start bringing some troops home from Afghanistan within two to four years.
Defence Minister John Faulkner says it depends on when the mission to train Afghan soldiers is completed.
Australian soldiers have been involved in training the Afghan National Army's 4th Brigade.
Senator Faulkner was announcing that the United States will lead Australian troops in a new multinational force in Afghanistan's Uruzgan province.
An Australian civilian is also expected to lead the reconstruction project in Uruzgan province after Dutch forces there withdraw.
The Dutch have been taking the lead role in Uruzgan but will pull out almost 2000 troops from the province in August.
Transition to 'overwatch' role envisaged
Senator Faulkner says he has received advice from Defence in which it is estimated that Australia will be able to hand over responsibility for security to Afghan forces within two to four years.
"I expect that we would adjust our force levels as the ADF mission transitions, if you like, from a training mission to an overwatch role," he says.
But he would not provide a "precise timetable" for withdrawal because, he says, the estimate is dependent on several factors.