DEFENCE Minister Marise Payne has confirmed the government will send an extra 30 troops to Afghanistan in response to a NATO request, bringing the total number of defence personnel in the country to 300.

Senator Payne announced the change at a Senate estimate hearing in Canberra on Monday.

"These additional ADF members will allow Australia to commit additional advisers to further develop the long-term capabilities of the Afghan security forces as part of our current train assist mission. Their role will be to continue in the train advise and assist roles," she said.

"Given the centrality of Afghanistan and the global fight against terrorism, and enhanced contribution to the support mission is both timely and appropriate.

"These adjustments have been considered by the government in light of broader ADF commitments across the globe and in view of the extremely dynamic strategic environment in which we currently find ourselves, not least in our own region.

The Australian government has been working to bolster its defence capabilities, announcing in the Federal Budget that the Australian Federal Police will receive $321 million over the next four years while ASIO will receive an additional $75 million to restore resources.