Australian Foreign Minister Bob Carr said that the government would not make any more representations to the US on the case as it "doesn't affect Australian interests", media reports said in Melbourne.
Carr was speaking before a Senate budget estimates committee Thursday.
Carr's announcement that he would not "over-service" Assange's consular needs follows after US military prosecutors disclosed that they regard the WikiLeaks chief not as a journalist dealing with sources but as a conspirator in the theft of classified information.
This week, US prosecutors targeted Assange alleging, at the opening of former US soldier Bradley Manning's trial, that he had directly encouraged and aided the soldier's massive leaks of classified documents.
US also alleged that Assange conspired with Manning in the theft of classified information, including advising the soldier on "finding ways to browse SIPRNET anonymously".
SIPRNET or Secret Internet Protocol Router Network is a system of interconnected computer networks used by the US Department of Defense and the US Department of State to transmit classified information including material classified as secret.
SIPRNET was one of the networks accessed by Manning as well as the source of the US diplomatic cables published by WikiLeaks in November 2010.
On a query if the government would inquire whether a US grand jury probing Assange was ongoing, Carr said no further inquiries would be made because "it doesn't affect Australian interests".
"I'm not going to have resources allocated to it," he said adding, "There's been enough investment of (department) resources in looking after Mr Assange's interests. This is an over-servicing of a consular case."
He said, "When information emerges from the American system it can be looked at with interest. It's not a focus of our diplomacy. Why would it be?"
Asked if the federal government would raise the question of Assange's free-speech protection as a journalist under the First Amendment to the US constitution, Carr said, "It wouldn't be a matter of concern to Australia to make a case for him. No, why would we do that?", reports said.
Australian-born Assange has taken refuge inside the Ecuadorian embassy in London, where he has been granted diplomatic asylum since June last year after the British government ordered his extradition to Sweden for his involvement in an alleged sex assault case.
Assange fears he may be subsequently extradited to the United States from Sweden to face charges over the diplomatic cables case.
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