Australian forces in Afghanistan will completely hand over control for security in Uruzgan province to local forces by the end of this year, although some troops will remain.
Defence Minister Stephen Smith cited a recent for today's announcement of a more definite transition timetable.
"For some time, the Prime Minister and I have been saying that our advice and our expectation was that transition in Uruzgan province itself would occur either by the end of 2013 or by the first quarter of 2014," Mr Smith told reporters in Perth.
"All of our advice and assessment and analysis and view is now that transition will be complete in Uruzgan province by the end of this year."
US president Barack Obama and his Afghan counterpart Hamid Karzai agreed to speed up the handover of combat operations in Afghanistan during a recent meeting in Washington.
Mr Obama said final decisions on this year's troop reductions and the post-2014 US military role were still months away, but his comments raised the prospect of an accelerated withdrawal timetable as the security transition proceeds - although precisely how much of an acceleration was unclear.
Australia's main involvement in Afghanistan is in Uruzgan province, where an average of 1,550 troops are deployed alongside civilian workers.
Mr Smith says the transition arrangements and the structure of Australia's operations in Afghanistan after that period will now be a priority for the Defence Force.
He says it is possible that Australia will provide a Special Forces contribution to the help meet the country's ongoing security needs, so long as it has an "appropriate mandate" to operate in Afghanistan.
Mr Smith also says he hopes to strike a long-term agreement with Afghanistan over issues including development assistance and trade.