(CNN) -- American intelligence leaker Edward Snowden applied for temporary asylum in Russia on Tuesday, Russian lawyer Anatoly Kucherena told CNN.

WikiLeaks, a group that facilitates the anonymous leaking of secret information through its website, also posted on its official Twitter account Tuesday that Snowden applied for a "temporary protection visa" in the country. Snowden is charged with espionage in the United States and apparently has been holed up in Moscow's Sheremetyevo International Airport for about three weeks.

Kucherena, a lawyer with a Kremlin advisory body, told the state-run news agency RIA Novosti that Snowden wrote the request in his presence and then gave it to a Federal Migration Service representative at the airport.

Snowden said Friday that he wanted temporary asylum in Russia while awaiting safe passage to Latin America, where he seeks longer-term refuge.

Snowden, a former National Security Agency contractor, left Hawaii for Hong Kong earlier this year and leaked documents to the media that exposed U.S. mass surveillance programs.

After he publicly identified himself as the leaker last month, he departed Hong Kong for Russia, where he is believed to have been staying in a transit area of the Moscow airport.

He technically has been a free man while at the airport but has been unable to travel after U.S. authorities revoked his passport when the United States charged him with espionage.

Snowden's application may be a shift in his position. About two weeks ago, he reportedly withdrew a request for asylum in Russia after Russian President Vladimir Putin said Snowden would need to "stop his work aimed at harming our American partners" if he wanted to stay in the country.

But on Friday, in a meeting with human rights activists and lawyers, Snowden reportedly said he wanted temporary asylum in Russia while waiting for passage to Latin America, and added that he will not harm the United States in the future.

The presidents of Venezuela and Bolivia have said their countries would give him asylum, and Nicaragua's president said he would offer it "if circumstances permit."

Over the weekend, a journalist who first published the leaked documents said that Snowden has more damaging information that could be a "nightmare" for the U.S. government.

Glenn Greenwald of The Guardian told an Argentine newspaper, La Nacion, that releasing more information to hurt the United States is not Snowden's goal. However, he said, Snowden has a "large number" of documents about software people use "without consciously agreeing to surrender their rights to privacy."

Snowden has given copies of the papers to several people, Greenwald told the paper, according to an English translation.

"The U.S. government should be on their knees every day praying that nothing happens to Snowden, because if something happens, all information will be revealed and that would be their worst nightmare," he said.

CNN"s Carol Jordan, Jason Hanna and Steve Almasy contributed to this report.