The Australian government has washed its hands of Julian Assange as prosecutors at the trial of US soldier Bradley Manning have openly targeted the WikiLeaks publisher as a conspirator engaged in espionage.

Foreign Minister Bob Carr has told a Senate budget estimates committee that the government would make no more representations to the US on Assange's circumstances because his case “doesn't affect Australian interests”.

Senator Carr's declaration that he would not “over-service” Assange's consular needs came after US military prosecutors left no doubt that they regard the WikiLeaks chief not as a journalist dealing with sources but as a conspirator in the theft of classified information

US prosecutors made repeated references to Assange this week, alleging at the opening of Private Manning's trial that the WikiLeaks publisher had directly encouraged and aided the soldier's massive leaks of classified documents.

The US has alleged that Assange conspired with Manning in the theft of classified information, including advising the soldier on "finding ways to browse SIPRNET [a secure database] anonymously”.

Fairfax Media has also learnt that Assange has been prevented by one of the largest banks in the US from making a donation to his own political party.

The Bank of America blocked the transfer to the new WikiLeaks Party of a $25,000 prize awarded to Assange by the Japanese musician, artist and philanthropist Yoko Ono.

News of the funding block against the WikiLeaks Party comes as the Department of Foreign Affairs and Trade acknowledged to the Senate estimates hearing that WikiLeaks, and by implication Assange, continued to be under investigation by the US Justice Department.

However, when asked by Greens senator Scott Ludlam whether the Australian government would raise the question of Assange's free-speech protection as a journalist under the First Amendment to the US constitution, Senator Carr said that “it wouldn't be a matter of concern to Australia to make a case for him. No, why would we do that?”

Asked whether the government would inquire whether a US grand jury investigation of Assange was ongoing, Senator 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. "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 added: “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?”

Ms Ono honoured Assange with her annual Courage Award for the Arts in New York in February for his "courageous step" in "returning what belongs to the public domain".

Assange asked that the $25,000 award be sent to the WikiLeaks Party, a separate legal entity to WikiLeaks. However, in April Ms Ono's office said the Bank of America had refused to wire the money to the party's account. Her office then paid the award to the US-based Freedom of the Press Foundation, which in turn passed it on to WikiLeaks.

The Bank of America is one of a number of major financial institutions including Visa, American Express, Mastercard and Western Union that since December 2010 have refused to transfer funds to WikiLeaks. Transfers have been allowed to WikiLeaks-related entities, including Assange's legal defence fund.

WikiLeaks Party president John Shipton said the party had not experienced problems with other financial institutions.

Assange is subject to a Swedish extradition warrant concerning sexual assault allegations and has been granted diplomatic asylum in the Ecuadorean embassy in London

Assange No Concern Of Ours, Says Carr