Gillard said Australia's timetable for a 2014 pull-out has been laid out clearly, and has not changed, according to the ABC news report.
"We are in transition now. That's a process that will take 12 to 18 months," she said, adding "what transition means is we are increasingly handing security leadership over to local Afghan forces, and we will see that mission through."
Gillard said Australia's involvement in Afghanistan had been worthwhile despite the deaths of its 38 soldiers.
"We went there for the right reason. We are acquitting an important mission in our national interest," she said.
"Every life lost hits us hard. It's a tragedy for our nation and particularly a tragedy for the families who lose loved ones.
"I've looked in people's eyes at those funerals, I've seen them wipe the tears away.
"I'm not, you know, in any denial about the cost.
"I've felt it. But, for our nation, in our national interest, it was right to go and it's right to stay there to get the job done.
"That's a tough call, but it's the call I've made and the Government's made and it's the right call."
New Zealand has confirmed its troops will end a decade- long deployment in Afghanistan's Bamiyan province at the end of April next year, five months earlier than originally planned.
The announcement came after five New Zealand soldiers were killed in Afghanistan in less than three weeks.
New Zealand's prime minister John Key said planning for the earlier withdrawal began before those deaths, explaining that New Zealand needed to remove its planes before a planned upgrade of the Bamiyan airport.
