SYDNEY: WikiLeaks founder Julian Assange's three-and-a-half-year stay in the Ecuadorian embassy in London amounts to 'unlawful detention', a United Nations panel examining his appeal will rule on Friday, the BBC reported.

Assange, a former computer hacker who has been holed up in the embassy since June 2012, told the UN Working Group on Arbitrary Detention that he was a political refugee whose rights had been infringed by being unable to take up asylum in Ecuador.

Read: UK police call off guard for Assange outside Ecuador embassy.

Reuters was unable immediately to confirm the BBC report and the UN said the panel's opinion, which is not legally binding, was due to be published on Friday. The British police said Assange would face arrest if he leaves the embassy.

The Australian, who jumped bail to take refuge in the embassy, is wanted in Sweden for questioning over allegations of rape in 2010, which he denies.

“Should the UN announce tomorrow that I have lost my case against the United Kingdom and Sweden, I shall exit the embassy at noon on Friday to accept arrest by British police as there is no meaningful prospect of further appeal,” Assange said in a statement posted on the Wikileaks Twitter account.

“However, should I prevail and the state parties be found to have acted unlawfully, I expect the immediate return of my passport and the termination of further attempts to arrest me.”

A decision in his favour would mark the latest twist in a tumultuous journey for Assange since he incensed the United States and its allies by using his WikiLeaks website to leak hundreds of thousands of secret US diplomatic and military cables in 2010, disclosures that often embarrassed Washington.

Assange, 44, fears Sweden will extradite him to the United States, where he could be put on trial over WikiLeaks' publication of the classified military and diplomatic documents, one of the largest information leaks in US history.

He made international headlines in early 2010 when WikiLeaks published classified US military video showing a 2007 attack by Apache helicopters that killed a dozen people in Baghdad, including two Reuters news staff.

Later that year, the group released over 90,000 secret documents detailing the US-led military campaign in Afghanistan, followed by almost 400,000 internal US military reports detailing operations in Iraq.

Those disclosures were followed by the release of more than 250,000 classified cables from US embassies.

It would go on to add almost three million more diplomatic cables dating back to 1973.

Political refugee?

In his submission to the UN working group, a body of outside experts, Assange argued that his time in the embassy constituted arbitrary detention.

Assange says he is the victim of a witch hunt directed by the United States and that his fate is a test case for freedom of expression.

He said that he had been deprived of his fundamental liberties, including lack of access to sunlight or fresh air, adequate medical facilities, as well as legal and procedural insecurity.

Per Samuelson, one of Assange's Swedish lawyers, said if the UN panel judged Assange's time in the embassy to be custody, he should be released immediately.

“It is a very important body that would be then saying that Sweden's actions are inconsistent with the European Convention on Human Rights. And it is international common practice to follow those decisions,” Samuelson told Reuters.

Since Assange's confinement, WikiLeaks has continued to publish documents on topics such as the Trans-Pacific Partnership, one of the world's biggest multinational trade deals, which was signed by 12 member nations on Thursday in New Zealand.