London (AFP) - WikiLeaks founder Julian Assange on Friday urged Britain to let him walk free from Ecuador's London embassy after a UN panel found that the anti-secrecy campaigner who faces a rape allegation in Sweden was "arbitrarily detained."
Speaking to a handful of supporters and a media scrum in a rare appearance from the balcony of the embassy where he took refuge nearly four years ago, Assange hailed a "victory of historical importance".
"How sweet it is! This is a victory that cannot be denied," he proclaimed, waving a hard copy of the legal opinion and often seeming emotional.
Assange has refused to go to Sweden for questioning fearing deportation to the US over WikiLeaks' release of 500,000 secret military files on the wars in Afghanistan and Iraq.
Earlier, the 44-year-old Australian told journalists via video link that it was "now the task of the states of Sweden and the United Kingdom as a whole to implement the verdict".
The UN panel said Assange's detention should end and that he should be able to claim compensation from Britain and Sweden.
But both countries quickly dismissed the non-binding legal opinion, with Britain's Foreign Secretary Philip Hammond calling it "ridiculous".
Assange walked into the embassy in June 2012 to avoid the threat of arrest and extradition to Sweden, where he still faces a rape allegation.
He has lived there ever since in a small office room with a bed, computer, sun lamp, treadmill and access to a small balcony decorated with Ecuador's flag.
In a statement, the panel said it had adopted an opinion that considered Assange "arbitrarily detained by the governments of Sweden and the United Kingdom of Great Britain and Northern Ireland."
It added: "The working group also considered that the detention should be brought to an end and that Mr Assange should be afforded the right to compensation."
- Fears of imprisonment -
Britain and Sweden sharply condemned the panel's findings and said they would change nothing.
Hammond called Assange "a fugitive from justice."
"This is frankly a ridiculous finding by the working group and we reject it," the foreign secretary added.
Sweden's foreign ministry said that it "does not agree" with the assessment.
"Mr Assange is free to leave the embassy at any point and Swedish authorities have no control over his decision to stay at the embassy," the ministry added.
Only three of the five members of the UN panel supported the opinion -- one recused herself because she is Australian, like Assange, and another member disagreed.
Christophe Peschoux, the working group's secretary, said at a briefing in Geneva that Britain and Sweden had two months to submit new information to force a review, and Britain says it will contest the opinion.
Ecuador's Foreign Minister Ricardo Patino said it was "time for both governments... to allow Julian Assange his freedom."
Swedish authorities want to speak to Assange about a rape allegation whose statute of limitations does not expire until 2020.
Elizabeth Fritz, the lawyer for the woman who has accused Assange, criticised the panel's comments.
"That a man who is wanted on an arrest warrant for rape should be awarded compensation for intentionally hiding from the judicial system for more than five years is offensive to my client," she said.
Swedish judicial authorities said last month that Ecuador had refused its request to let a Swedish prosecutor question Assange because Quito wanted an Ecuadorean prosecutor to do the questioning.
- 'Publicity stunt' -
Assange fears that if he went to Sweden for questioning, he could then be sent to the US and face prison.
WikiLeaks' activities -- including the release of 500,000 secret military files on the wars in Afghanistan and Iraq -- have infuriated the US.
The main source of the leaks, US Army soldier Chelsea Manning, was sentenced to 35 years in prison for breaches of the Espionage Act.
A hero to supporters and a dangerous egocentric to detractors, the computer programmer and hacker, whose celebrity fans include fashion designer Vivienne Westwood and singer Lady Gaga, founded WikiLeaks in 2006 and has been portrayed in two movies in recent years.
Britain spent over Â£10 million (12 million euros, $15 million) maintaining a 24-hour guard outside the embassy to immediately arrest Assange if he set foot on British soil, but withdrew it last year.
The Assange case has polarised opinion in Britain and there were many criticisms of his conduct Friday.
The Guardian newspaper, which has in the past worked with WikiLeaks to publish secret documents, used an editorial to condemn the latest developments as "a publicity stunt."