"If I could go any place in the world, that place would be home," Snowden said almost a year to the day since he revealed a stunning US surveillance dragnet mining data from phones and internet companies around the world.
"From day one, I said I'm doing this to serve my country. Whether amnesty or clemency is a possibility, that's for the public to decide," he told NBC in his first interview with US television since the scandal broke in early June last year.
And he sought to defend himself against charges led by the US administration that he is a traitor who endangered lives by revealing the extent of an NSA spying program through the British daily, The Guardian.
"The reality is the situation determined that this needed to be told to the public. You know, the constitution of the United States has been violated on a massive scale."
But top US officials laughed off the idea of a clemency, with Secretary of State John Kerry saying the 30-year-old former CIA employee should "man up" and return to face trial.
Snowden said he had worked covertly as "a technical expert" for the Central Intelligence Agency and the National Security Agency, and as a trainer for the Defence Intelligence Agency.
"I don't work with people. I don't recruit agents. What I do is, I put systems to work for the United States. And I've done that at all levels — from the bottom on the ground all the way to the top."
But National Security Advisor Susan Rice swiftly denied his contention, replying "no" when asked by CNN if he had been a highly-trained undercover spy.
"Edward Snowden was a contractor working for the NSA and other elements of the intelligence community," she reiterated, stressing he should return home to face justice.
Snowden however blamed the United States for forcing him into exile in Russia after his revelations.
"The reality is, I never intended to end up in Russia," he said in the interview recorded clandestinely last week in Moscow.
"I had a flight booked to Cuba onwards to Latin America and I was stopped because the United States government decided to revoke my passport and trap me in Moscow Airport," Snowden told NBC.
"So when people ask, 'Why are you in Russia?' I say, please, ask the State Department."
But Kerry hit back, saying Snowden should do the patriotic thing and return to the United States to face espionage charges for leaking a trove of classified documents.
"This is a man who has betrayed his country," Kerry told CBS News. "He should man up and come back to the US."
"The fact is, he has damaged his country very significantly. I find it sad and disgraceful."
Snowden was granted asylum by Russia in August 2013 after spending weeks holed up in Moscow's Sheremetyevo Airport after flying in from Hong Kong.
Kerry, however, denied that the State Department had trapped Snowden in Moscow, saying "for a supposedly smart guy, that's a pretty dumb answer, frankly."
"If Mr Snowden wants to come back to the United States today, we'll have him on a flight today," Kerry told NBC.
The temporary asylum expires August 1 and Snowden said "if the asylum looks like it's going to run out, then, of course, I would apply for an extension."
He denied he was a traitor, saying he was a patriot and insisting that a year on the administration could not show a single example of someone who had been harmed by his revelations.