Washington - Fugitive self-proclaimed spy Edward Snowden said on Wednesday he wants to return home, as he defended his massive leak of US intelligence secrets, saying abuses of constitutional rights left him no choice.
"If I could go anywhere 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, including Europe.
"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 hacker and a traitor who endangered lives by revealing the extent of the NSA spying programme 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," he said.
"How can it be said that this harmed the country when all three branches of government have made reforms as a result?" Snowden asked, looking relaxed and calm during the interview in a Moscow hotel.
But top US officials laughed off the idea of a clemency. Secretary of State John Kerry said the 30-year-old former CIA employee should "man up" and return to face trial.
Snowden also alleged he was not just a low-level contractor working for the CIA, as the White House has repeatedly insisted.
"I was trained as a spy in sort of the traditional sense of the word in that I lived and worked undercover overseas - pretending to work in a job that I'm not - and even being assigned a name that was not mine," he told NBC.
Snowden said he had worked covertly as "a technical expert" for the Central Intelligence Agency and the National Security Agency (NSA).
But National Security Advisor Susan Rice disputed his contention, replying "no" when asked by CNN if he had been a highly-trained undercover spy.
Snowden however blamed the United States for forcing him into exile in Russia.
"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.
"For a supposedly smart guy, that's a pretty dumb answer, frankly," Kerry hit back.
Snowden should do the patriotic thing and return to the US to face espionage charges for leaking hundreds of thousands of classified documents, the top US diplomat said.
"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, having flown in from Hong Kong.
He says he cannot return to face trial because of the "extraordinary charges" laid against him which would bar him from using classified information in his defence.
Snowden said he had had no contact with Russian President Vladimir Putin since he was given in asylum, and denied he was being paid by the Russian government.
And he said he missed his family, colleagues and his work, insisting he was a patriot, still serving the US government.
"Sometimes to do the right thing you have to break a law," he insisted.
"Being a patriot doesn't mean prioritising service to government above all else. Being a patriot means knowing when to protect your country, knowing when to protect your constitution," Snowden added.
"If Mr Snowden wants to come back to the United States today, we'll have him on a flight today," Kerry told NBC.
His temporary asylum expires 1 August and Snowden said "if the asylum looks like it's going to run out, then, of course, I would apply for an extension".
"I may have lost my ability to travel, but I have gained the ability to go to sleep at night, put my head on the pillow and feel comfortable that I have done the right thing even when it was the hard thing. I'm comfortable with that," Snowden concluded.