The Department of Defence has concluded that classified Afghanistan war documents released by WikiLeaks in July did not significantly expose operations or impact Australia's national interests.

It came as the taskforce started an investigation into last week's leak by the controversial website of 400,000 classified documents on the Iraq war.
"This [new] investigation will take some time, given the volume and complexity of the material," a spokesman said.
"The findings of this investigation will also be released in due course."
The taskforce was created in late July to "ensure that as a result of the leaking of the materials, steps were taken by Defence to mitigate any risks to Australians, our partners, those with whom we work including in the local community, and our ongoing operations".
It found that materials on the Afghan war were "predominantly tactical-level reporting, the majority of which was low-level operational reporting of activities such as patrols, community engagement and routine operational activities".
While the documents "would not routinely be made public by Defence for operational security reasons", the taskforce found that much of the detail had already been officially reported "in greater detail than in the leaked materials."
"The investigation found that the leaked documents have not had a direct significant adverse impact on Australia's national interests," it said.
"Operational areas of Defence have confirmed that necessary measures have been taken to mitigate against risks to operational security."