Ecuador 'analyzing' request
It seems unlikely that Cuba, Venezuela or Ecuador -- the nations on Snowden's potential itinerary -- would be inclined to send him back to the United States.
The U.S. government has already asked those three Latin American countries to not admit Snowden or to expel him if they do, a senior Obama administration official told CNN on Sunday.
But Cuba and Venezuela have long had strained relations with Washington. And Ecuador has given Assange refuge in its embassy in London for a year after he unsuccessfully fought extradition to Sweden in British courts.
Assange say he fears Sweden, which wants him for questioning about sexual assault allegations, would transfer him to the United States.
In his letter, read by Patino, Snowden compared himself to Pvt. Bradley Manning, the U.S. soldier accused of leaking classified information through WikiLeaks.
He said U.S. officials have treated Manning inhumanely by holding him in solitary confinement, and he predicted a similar "cruel and unusual" fate for himself if he falls into U.S. hands.
Assange, speaking to reporters on a conference call, accused the United States of trying to bully other nations into handing over Snowden, whom he referred to as a "whistle-blower who has told the public an important truth."
"The Obama administration was not given a mandate by the people of the United States to hack and spy upon the entire world, to breach the U.S. Constitution and the laws of other nations in the manner that it has," Assange said. "To now attempt to violate international asylum law by calling for the rendition of Edward Snowden further demonstrates the breakdown in the rule of law by the Obama administration, which has sadly become so familiar to so many."
Assange said WikiLeaks aided Snowden in his asylum applications and is paying for his travels.
The Ecuadorian government is "analyzing" Snowden's asylum request "with a lot of responsibility," Patino earlier told reporters in Hanoi, Vietnam.
"It has to do with the freedom of expression, with the security of citizens around the world, and therefore we have to analyze it deeply," Patino said.
U.S. warns China
Hong Kong's decision to let Snowden leave dealt efforts to build trust between the United States and China a "serious setback," Carney said Monday.
Hong Kong, a semi-autonomous Chinese territory, allowed Snowden to leave Sunday after declining to act on a U.S. request for a provisional arrest warrant, saying it needed more information.
Without that information, the Hong Kong government said, it had no reason to stop him from getting on the plane to Moscow.
Although Assange said Monday that Snowden traveled out of Hong Kong on refugee papers issued by Ecuador, Carney said U.S. officials had told Hong Kong authorities that Snowden's passport had been revoked "in plenty of time to have prohibited travel."
"We are just not buying that this was a technical decision by a Hong Kong immigration official," Carney said Monday. "This was a deliberate choice by the government to release a fugitive despite a valid arrest warrant, and that decision unquestionably has a negative impact on the U.S.-China relationship."
Carney declined to speculate what impact the decision could have on U.S.-China relations, but said U.S. officials are making their displeasure known "very directly."
The surveillance controversy
Snowden has acknowledged that he leaked classified documents about the National Security Agency's surveillance programs to the Guardian newspaper in Britain and to The Washington Post. The documents revealed the existence of programs that collect records of domestic telephone calls in the United States and monitor the Internet activity of overseas residents.
Snowden gave up a comfortable life "in order to bring to light what he believed was serious wrongdoing on the part of our political officials," said Glenn Greenwald, the Guardian columnist who co-authored the stories. "And he's now at best going to spend the rest of his life on the run from the most powerful government on Earth."
The disclosures shook the U.S. intelligence community and raised questions about whether the NSA is eroding American civil liberties.
Snowden told the Guardian that he exposed the surveillance programs because they pose a threat to democracy, but administration officials said the programs are vital to preventing terrorist attacks and are overseen by all three branches of government.
"We have not in a single case had a place where a government official engaged in willful effort to circumvent or violate the law. Zero times have we done that," Gen. Keith Alexander, the NSA's director, said on ABC's "This Week."