US Secretary of State John Kerry invited Snowden to "man up and come back to the United States."
"The bottom line is this is a man who has betrayed his country, who is sitting in Russia, an authoritarian country where he has taken refuge," Kerry told the CBS network.
"If he has a complaint about what's the matter with American surveillance, come back here and stand in our system of justice and make his case," Kerry said.
More top news
The two brightest planets in the solar system will appear close to collision tonight, an illusion caused by line of sight.
US superstore apologises after a customer who had his request for a Confederate flag cake rejected managed to get an ISIS flag cake instead.
After Heather Watson becomes the latest tennis star reprimanded for 'audible obscenity', we ask - what happens to the players who swear?