Former US National Security Agency contractor Edward Snowden told a US television interviewer he was not under the control of Russia's government and had given Moscow no intelligence documents after nearly a year of asylum there.
"I have no relationship with the Russian government at all," Snowden said in an interview with NBC News, his first with a US television network. "I'm not supported by the Russian government. I'm not taking money from the Russian government. I'm not a spy."
The remarks by Snowden, whose leaks about highly classified US surveillance programs shook the NSA and prompted limited reforms by President Barack Obama, were his most extensive to date on his relations with his host government.
Current and former US intelligence officials have said it is unlikely Russian security services have not squeezed Snowden for secrets.
"I think he is now being manipulated by Russian intelligence," former NSA director Keith Alexander said last month.
But Snowden - who said he wants to return to the United States - said he destroyed classified materials before transiting to a Moscow airport, where he was prevented from onward travel.
"I took nothing to Russia, so I could give them nothing," he told NBC's Brian Williams in the hour-long interview.
Later in the interview, Snowden briefly criticised the crackdown on freedom of expression under Russian President Vladimir Putin.
Casting himself as a defender of privacy and civil liberties, he deemed it "frustrating" to "end up stuck in a place where those rights are being challenged in ways that I would consider deeply unfair."
Snowden, who fled to Hong Kong and then Moscow last year, is believed to have accessed about 1.5 million secret documents, US officials have said, although how many he actually took is unclear. The leaked documents revealed massive programs run by the NSA that gathered information on emails, phone calls and Internet use including, in many cases, by Americans.
He was charged last year in the United States with theft of government property, unauthorised communication of national defence information and willful communication of classified intelligence to an unauthorised person.
"If I could go anywhere in the world, that place would be home," Snowden said.
US officials said he was welcome to return to the United States if he wanted to face justice for leaking details of massive US intelligence-gathering programs.
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 "This Morning" program on Wednesday.
Snowden made clear he would not return to the United States and hope for the best. He said he would not simply "walk into a jail cell," and that if his one-year asylum in Russia, which expires on Aug. 1, "looks like it's going to run out, then of course I would apply for an extension."
The Guardian newspaper quoted Ben Wizner, a lawyer for the American Civil Liberties Union and legal adviser to Snowden, responding to Kerry's comments. Wizner said it would be impossible for Snowdon to argue that his disclosures had served the common good if he returned home to face the current Espionage Act charges.
He also said Snowden would run the risk of facing numerous additional charges for each document that has been published.
"The exposure that he faces is virtually unlimited under this," Wizner said.
In one odd moment in the NBC interview, Snowden expressed sympathy for working-level NSA employees who have been castigated as a result of his leaks.
"People have demonised the NSA to a point that's too extreme," he said, adding that the problem is with senior-level officials who expand their surveillance powers without public debate.