Evading arrest from the safety of a balcony, WikiLeaks founder Julian Assange appeared in public Sunday for the first time since he sought refuge inside Ecuador’s embassy in London.

British police officers stood guard as Assange urged the United States to “renounce its witch hunt” against the whistle blowing website, which has leaked thousands of classified documents.

“The United States must vow that it will not seek the prosecution of our staff or our supporters,” Assange told several hundred people who gathered outside the embassy. “The U.S. administration’s war upon whistleblowers must end.”

Reading from a written statement, Assange urged the U.S. to halt an FBI probe into WikiLeaks.

The White House declined comment Sunday, but on Saturday it said Assange's fate is an issue for Sweden, Britain and Ecuador to resolve.

Assange retreated into the embassy two months ago in an attempt to avoid extradition to Sweden, where he is wanted for questioning on sexual misconduct allegations.

The 41-year-old was formally granted political asylum on Thursday. If he steps outside the confines of the red-brick building in London’s Knightsbridge area, Assange risks arrest.

“We will not allow Mr. Assange safe passage out of the United Kingdom,” said William Hague, the U.K. foreign secretary.

The small, white-railed balcony Assange appeared on is legally considered part of Ecuador’s mission and places the computer whiz just barely out of the reach of police.

Assange thanked Ecuadorian President Rafael Correa Sunday for “for the courage he has shown” in granting him political asylum, as well as the nation’s Foreign Minister Ricardo Patino.

Ecuador maintains it’s attempting to protect Assange from any attempts at prosecution over WikiLeaks, while the U.K. says it must follow through on a European arrest warrant.

In his speech, the WikiLeaks founder also thanked several Latin American countries -- including Argentina, Bolivia, and El Salvador – for defending the concept of political asylum.

He also thanked supporters for holding a vigil outside the Ecuadorian embassy.

“The next time somebody tells you that it is pointless to defend those rights that we hold dear, remind them of your vigil,” he said. “Remind them how in the morning, the sun came up on a different world and a courageous Latin American nation took a stand for justice.”

Former Spanish Judge Baltasar Garzon, who is representing Assange, said Sunday that Ecuador could consider making an appeal to the International Court of Justice in the Hague to compel Britain to grant Assange safe passage out of the country.

Supporters maintain that the allegations against Assange in Sweden are part of a ploy to make him stand trial for his work with WikiLeaks. That theory is disputed by the two women who accused him of sexual assault during a trip to Sweden in 2010.

Assange has not been formally charged with any offence.

In his Sunday speech, he also urged the United States to release Pfc. Bradley Manning, an army private accused of “aiding the enemy” by leaking classified documents to WikiLeaks.

Manning, who is still awaiting trial, faces the possibility of life in prison if a court finds that he leaked hundreds of thousands of diplomatic cables and war logs to the website.

"If Bradley Manning really did as he is accused, he is a hero, an example to us all, and one of the world's foremost political prisoners,” said Assange.

With files from The Associated Press