Story highlights Julian Assange speaks from the Ecuadorian Embassy in London

"It is time for the United States to cease its persecution of WikiLeaks," Assange says

Ecuador's foreign minister urges Assange be granted safe passage out of the embassy

The founder of WikiLeaks delivered an impassioned appeal Wednesday for the U.S. government to end its actions against him, his website and those who support it.

"It is time for the United States to cease its persecution of WikiLeaks, to cease its persecution of our people and to cease its persecution of our alleged sources," Julian Assange, speaking via satellite from London, told a packed conference room at the United Nations, where world leaders were attending the United Nations General Assembly.

"It is time for President Obama to do the right thing and join the forces of change -- not in fine words, but in fine deeds."

Assange was speaking from the Ecuadorian Embassy in London, where he has been holed up since June.

The event was held by the Mission of Ecuador on U.N. grounds, but was not officially sponsored by the world body.

For much of 2011 until June, Assange had been under house arrest in Britain while he filed appeals against his extradition from Britain to Sweden. Sweden has said it wants to question Assange on allegations that he sexually assaulted a woman there.

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Assange has not been charged with a crime.

Ecuador's foreign minister, Ricardo Patino, said he planned to meet Thursday with British Foreign Secretary William Hague in an attempt to persuade him to allow Assange to leave the embassy without facing the possibility of arrest.

"We hope for a positive dialogue seeking a solution to this problem," Patino said. "There are many ways to assure a solution that will protect his life and human rights."

Ecuador granted Assange asylum in August, but he faces arrest in Britain if he leaves its embassy. The embassy is a sovereign space that authorities from other countries cannot encroach. In August a London policeman was photographed carrying an arrest plan for Assange

Assange has denied the sex allegations, describing them as a ruse to get him to Sweden, which would then extradite him to the United States.

Several U.S. officials have asserted that Assange violated the law by publishing in 2010 and 2011 a trove of classified war documents and diplomatic cables.

Patino said Swedish and British authorities have refused to accept his offer to allow Assange to be questioned in the embassy and refused to guarantee that he would not be extradited to a third country if he were to leave the embassy.

"U.S. law would likely grant someone in Mr. Assange's position asylum," said Baher Azmy, legal director of the New York-based Center for Constitutional Rights, which is representing him.

"But, of course, he is Julian Assange, and that means, in the United States, he is public enemy number one and a so-called enemy of the state and is therefore unlikely to get a fair trial -- even for conduct that is and should be protected by the United States Constitution."

Prior to Wednesday's meeting, Azmy had cited the treatment of Bradley Manning, a U.S. soldier accused of leaking documents to WikiLeaks. "Based on how Bradley Manning has been treated, we have every reason to be concerned that Assange would be subject to brutal and inhumane treatment."

As of Wednesday, Assange said, Manning had been detained without trial for 856 days -- more than seven times the legal maximum of 120 days.

The first WikiLeaks leak, published in late summer 2010, was called the "Afghan War Diary."