The Australian authorities say they are seeking consular access to an Australian lawyer held in Libya after trying to meet Saif al-Islam, son of the late leader Muammar Gaddafi.
Defence lawyer Melinda Taylor is one of four members of the International Criminal Court's staff detained in the Libyan town of Zintan since Thursday.
Locals are suspicious about documents she tried to pass to Saif al-Islam.
ICC president Sang-Hyun Song has urged Libya to release the four immediately.