WikiLeaks founder Julian Assange has made a rare appearance on the balcony of the Ecuadorian Embassy after launching an attack against the Government for its "insulting" response to a UN working group report on his detention.
Foreign Secretary Philip Hammond branded the working group's findings on the "arbitrary detention" of Mr Assange as "frankly ridiculous" and said the Australian was "hiding from justice".
He spoke out after the UN panel had ruled Mr Assange was being "arbitrarily detained" in the embassy in London - and called for him to be paid compensation.
The UN Working Group on Arbitrary Detention said the Swedish and British authorities should end Mr Assange's "deprivation of liberty" and respect his physical integrity and freedom of movement.
Mr Assange spoke via Skype to a press conference in London, saying the UN report had brought a smile to his face, and insisting his detention had now been formally ruled as unlawful.
He said comments by Mr Hammond were "beneath" the minister's stature and insulting to the UN.
He later spoke to a crowd of his supporters from the embassy's balcony, holding up a copy of the UN report and saying he had won a "sweet victory" which the UK and Swedish authorities could not deny.
"What right do the governments of the US, UK or Sweden have to deny my children their father for five and a half years," he said to cheers from a small crowd of supporters.
He said he had become "tough" through what had happened to him over the past few years, but spoke of his children, saying they had nothing to do with the case.
"It is time they had their father back. That will happen, one way or another."
He is wanted for questioning in Sweden over a sex allegation, which he has always denied. He believes he will be taken to the United States for questioning over the activities of WikiLeaks if he is extradited.
He told the news conference that the UN Working Group's decision was legally binding, insisting there was no higher authority on whether detentions were lawful.
"It is insulting for the UN to call the decision ridiculous. Those comments were beneath the stature of a foreign minister."
Mr Assange said Sweden and the UK had opportunities in the past few weeks to appeal against the decision but had not taken any action, so the matter was now a "settled law".
Mr Assange said: "It is the end of the road for legal arguments by the UK and Sweden. Those arguments lost and the time for an appeal is over.
"It is now the task of the states of the UK and Sweden to implement the verdict. They cannot pretend to look tough."
He finished his comments by saying he missed his family, adding: "We have a really strong victory that has brought a smile to my face and I hope many others as well."
Melinda Taylor, part of Mr Assange's legal team, said the UN report made clear that the WikiLeaks founder was neither a fugitive from justice, nor could he just walk out of the embassy.
She called it a "damning indictment" of the way Mr Assange has been treated and showed his willingness to co-operate with the Swedish investigation.
Baltasar Garzon, another member of the legal team, told the news conference: "It is imperative they (UK and Sweden) respect the decision", adding that it was "mandatory to comply".
But Mr Hammond said: "I reject the decision of this Working Group. It is a group made up of lay people and not lawyers.
"Julian Assange is a fugitive from justice. He is hiding from justice in the Ecuadorian embassy.
"He can come out any time he chooses ... But he will have to face justice in Sweden if he chooses to do so.
"This is, frankly, a ridiculous finding by the working group and we reject it."