The Australian Department of Foreign Affairs does not believe a United Nations panel's ruling that Julian Assange is being "arbitrarily detained" is legally binding.

Nor has it made any representations to the British or Swedish governments about the ruling.

Department official Jon Philp told a Senate Estimates hearing in Canberra that no representations have been made to Sweden about Assange's case since December 2011.

"He is receiving due process under those legal systems," he said.

The 44-year-old Australian is likely to remain holed-up in the Ecuadorian Embassy in London after the UK and Swedish governments rejected the UN's ruling in early February.

Greens Senator Scott Ludlam queried why Australia considered the same UN panel's ruling on Burmese democracy icon Aung San Suu Kyi as legally binding.

"Legal issues are always decided on a case-by-case basis," department secretary Peter Varghese said.

Senator Ludlam said it was good enough for the Burmese, Iranian, and Maldives authorities to respect the panel's findings but Australia was going to give a "free pass to the British government".

"That's commentary," Varghese responded.

The department said the UK authorities are legitimately holding Assange's passport, and Australia would not seek to intervene.

Foreign Minister Julie Bishop has offered the WikiLeaks founder consular assistance, and is seeking legal advice about the implications of the UN panel ruling.

Three allegations of sexual assault in Sweden were dropped against Assange last year, when they reached their five-year statute of limitations.

However, Swedish prosecutors still want to question him over a 2010 rape allegation. Assange has denied all allegations.

In its ruling last week, the Human Rights Council Working Group on Arbitrary Detention found in favour of Assange.

"Assange has not been guaranteed the international norms of due process and the guarantees to a fair trial," it said. "Assange's stay at the Embassy of the Republic of Ecuador in London to this date should be considered as a prolongation of the already continued deprivation of liberty that had been conducted in breach of the principles of reasonableness, necessity, and proportionality."

The panel said the situation is excessive and unnecessary, and in contravention of two articles of the Universal Declaration of Human Rights and six articles of the International Covenant on Civil and Political Rights.

"The Working Group considers that, taking into account all the circumstances of the case, the adequate remedy would be to ensure the right of free movement of Mr Assange and accord him an enforceable right to compensation," it said.

Last week, Assange said he would hand himself over to British and Swedish authorities if the United Nations panel announced he had lost his case.

Assange has been living in the Ecuadorian embassy in London for more than three years, having been granted political asylum by the Ecuador government after failing to win his battle against extradition to Sweden in the UK courts.

During the lead-up to the 2013 Australian election, Assange launched the WikiLeaks Party in an attempt to secure a Senate seat in Victoria. After failing to secure a Senate place anywhere in Australia, the party was deregistered by the Australian Electoral Commission in July last year.

With AAP