"The only channels that Australia currently has available are diplomatic channels and those channels are being used," Roxon told Assange's lawyer, Jennifer Robinson, during an open session at a legal conference in Sydney.
Attorney-General Nicola Roxon said Canberra was asking "plenty of questions" about Assange, an Australian citizen, though it could not interfere in European proceedings involving the WikiLeaks chief.
Assange is under house arrest in Britain awaiting judgment from the Supreme Court in London on whether he can be extradited to Sweden for questioning over allegations of rape and sexual assault.