Australia will deploy another 30 troops to Afghanistan to help train local soldiers in their fight against Taliban militants.
NATO has asked all its member countries to re-examine their contributions, deciding it needs several thousand more foreign troops to advise the Afghan army.
The 30 extra soldiers will bring the total Australian contribution in Afghanistan to 300.
They are there to train and advise the local force, now grappling with a resurgent Taliban.
Australia has promised to keep troops in the country until at least next year.
But Defence Minister Marise Payne says that date is under constant review.
"The one thing we cannot afford to do is to allow terrorism to take further and greater root in Afghanistan and then continue to spread its tentacles elsewhere."
The extra soldiers will be provided in response to a request from NATO around a month ago, although the organisation did not ask for a specific number.
The general in charge says the mission is short by a few thousand troops and has asked all member countries to consider sending more.
Australia is a non-member contributor to the United States-led coalition.
Former army chief Peter Leahy (lay) says the local fighting force still clearly needs international help.
"Frankly, the Afghan army isn't a particularly happy place. The levels of desertion are fairly high. They're taking a lot of casualties, and they're seeing the country being challenged. And we see that the Taliban and some of the terrorist groups, almost at will, at any time and place of their choosing, can mount an attack. So, we do need to advise."
But not everyone supports the bolstering of troop numbers.
Independent MP and former spy Andrew Wilkie says the war in Afghanistan has already been lost.
He says sending more troops will only inflame the situation.
"If we want to diminish the risk of terrorism within Australia, we should focus on our national interest, and we should pull the almost 300 soldiers out of Afghanistan, and we should pull the well over a thousand soldiers that are engaged further west in the Middle East. I mean, that would be good foreign-security policy. Again, it just comes down to the fact that, whatever the US wants, we deliver."
Meanwhile, coalition is investigating how one of its air strikes killed more than a hundred civilians in Iraq.
Australian Defence Force chief Mark Binskin has told a Senate Estimates hearing no Australian aircraft were involved in the strike in the city of Mosul in late March.
"While no Australian aircraft were involved in this incident in Mosul, we're working with our partners to assess the extent at which Australian personnel were involved in the coalition approval process."
US military officials say Iraqi troops requested the strike.
