Australia is to take lead responsibility for security in Afghanistan, in the southern province of Uruzgan from the United States a month early.
Defence minister Stephen Smith says it's happening slightly sooner than expected, as all the training with the US has been completed.
The ABC reports the changeover had been scheduled for November, but Mr Smith said it will now be next month.
"We've agreed to take over the leadership of combined team Uruzgan that's had an American leadership for some time," he said.
"We've been looking at November, but we've done all the training together with the United States and we think we will take over in October, so it's imminent."