SENIOR Defence Department officials feared the WikiLeaks exposé of secret US military reports would undermine public support for the Australian Defence Force in Afghanistan, according to newly released briefing papers.

Reports about a corrupt Afghan warlord who works closely with Australian special forces were considered particularly sensitive.

WikiLeaks ... threatened public support for the Australian Defence Force in Afghanistan.

More than two years after WikiLeaks published more than 75,000 leaked US reports on Afghanistan, the Defence Department has finally released, under freedom-of-information law, its assessment of the massive security breach.

In a confidential brief submitted to the former defence minister John Faulkner, Defence warned that WikiLeaks's July 2010 release of the ''Afghan War Logs'' was a matter of high political sensitivity that "could adversely affect public perceptions of the [International Security Assistance Force] campaign, [and] ADF operations in Afghanistan''.