Snowden has applied for asylum in Venezuela, Bolivia and 18 other countries, according to WikiLeaks, a secret spilling website that has been advising him. Many European countries on the list - including Austria, Finland, Ireland, the Netherlands, Norway, Spain and Switzerland - said he would have to make his request on their soil.

One of Snowden's best chances of finding refuge outside the United States may hinge on Venezuelan President Nicolas Maduro, who was also in Russia on Tuesday.

Maduro told Russian reporters that his country has not received an application for asylum from Snowden and dodged the question of whether he would take him with him when he left.

But Maduro also defended the former National Security Agency systems analyst.

"Who must protect Snowden? This is the question. This young man of 29 was brave enough to say that we need to protect the world from the American imperial elite, so who should protect him?" Maduro said in response to a question from journalists covering a ceremony to rename a Moscow street after Chavez. "All of mankind, people all over the world must protect him."

Maduro was scheduled to spend Wednesday in neighboring Belarus before returning to Venezuela.

In Venezuela, Foreign Minister Elias Jaua said that changing the flight's route without checking on how much fuel it had endangered Morales' life.

"All the countries that have denied permission for the flight of our brother president, Evo Morales, must be held responsible for his life and his dignity as president."

Another possible landing spot for Snowden is Ecuador, where Wikileaks founder and publisher Julian Assange has been seeking asylum.

"We are willing to analyze Mr. Snowden's request for asylum and this position has not changed," said Ecuadorean Foreign Minister Ricardo Patino on Tuesday. "What we have said is that we will be able to analyze the request when Mr. Snowden is in Ecuadorean territory or in an Ecuadorean mission."

Patino added that two weeks ago a hidden microphone was found in Ecuador's embassy in London, where Assange is holed up. "We want to find out with precision what the origin of the apparatus is."

Snowden, who recently turned 30, withdrew a bid for asylum in Russia when he learned the terms Moscow had set out, according to Putin's spokesman Dmitry Peskov. Putin said on Monday that Russia was ready to shelter Snowden as long as he stopped leaking U.S. secrets.

At the same time, Putin said he had no plans to turn over Snowden to the United States.

Rebuffed by Russia's president, the Obama administration has recently toned down demands Snowden be expelled from the Moscow airport in a sign that the U.S. believes he is not worth scuttling diplomatic relations between the former Cold War enemies.

On Monday, WikiLeaks posted a statement attributed to Snowden on its website, in which he slams Obama for "using citizenship as a weapon."

"Although I am convicted of nothing, (the United States) has unilaterally revoked my passport, leaving me a stateless person," Snowden says in the statement. "Without any judicial order, the administration now seeks to stop me exercising a basic right. A right that belongs to everybody. The right to seek asylum.

"Their purpose is to frighten, not me, but those who would come after me."