UPDATED: 4:40 p.m. GMT

LONDON — WikiLeaks founder Julian Assange said a UN decision that he should be allowed to move freely without arrest was a "vindication," and he criticised the Swedish and British governments for their objection to the decision.

"There is no ability to appeal the decision of the United Nations. The lawfulness of my detention or otherwise is now settled," Assange said, speaking from the Ecuadorian embassy where he has been holed up for almost four years on Friday afternoon via videolink at a news conference.

"I consider the outcome in this case to be vindication," Assange said.

Later in the afternoon, he appeared at a balcony at the embassy in London's Knightsbridge and addressed a gathered crowd. "This is a victory of historical importance," he said, thanking his supporters.

He accused the British, Swedish and American governments of denying his children their father for five-and-a-half years. "My children are completely innocent parties. It’s time that they had their father back and that will happen," he said.

Julian Assange on a screen as he addresses media from the embassy of Ecuador. Image: Frank Augstein/Associated Press

The United Nations Working Group on Arbitrary Detention said earlier Friday that Assange has been arbitrarily held since his arrest in London in Dec. 7, 2010, over allegations of sex crimes. It called on the British and Swedish governments to end his "deprivation of liberty," allow him to move freely and afford him the right to compensation for his suffering.

Assange's lawyer, Melinda Taylor, said he is the "victim of a significant miscarriage of justice."

The panel's decision doesn't legally require the governments to lift or not serve the arrest warrant on Assange, but it would support his case for being allowed to move freely.

The UK Foreign Office rejected the UN group's decision and said they will contest it. Foreign Secretary Philip Hammond said the decision was "ridiculous" and that Assange was a "fugitive from justice."

"An allegation of rape is still outstanding and a European Arrest Warrant in place, so the UK continues to have a legal obligation to extradite him to Sweden," the government said in a statement.

"We are deeply frustrated that this unacceptable situation is still being allowed to continue," the government said.

Assange said the governments had known about the decision for two weeks, and that that was there chance to appeal but they didn't. He said the nations would lose respect in the international community and there would be consequences for going against UN wishes.

Assange has been holed up in the embassy for almost four years as he has received political asylum from Ecuador. He has technically been allowed to leave but British authorities say they will arrest him.

Early Thursday morning, Assange issued a statement via the WikiLeaks Twitter account that if the UN panel ruled against him, he would walk out of the embassy at noon Friday and accept arrest. As the Swedish and British governments had knowledge of the UN's decision ahead of time, it is likely he made his bold statement because he knew how the panel would rule.

Assange: I will accept arrest by British police on Friday if UN rules against me. More info: https://t.co/Mb6gXlz7QS pic.twitter.com/mffVsqKj5w — WikiLeaks (@wikileaks) February 4, 2016

Assange took refuge in the Ecuadorian embassy in London's Knightsbridge on June 19, 2012, and applied for political asylum. He faces extradition to Sweden for questioning about alleged sex crimes, which he denies. He hasn't been charged in Sweden but the warrant for his arrest to be questioned over the crimes is still outstanding, after Assange lost legal challenges against it.

Assange has expressed fears that if he is sent to Sweden he will be extradited to the United States. His supporters say an investigation is still under way following WikiLeaks' publication of U.S. diplomatic cables and documents on the war in Afghanistan.