Athens, Greece: Edward Snowden, in exile in Moscow after leaking US National Security Agency documents, said on Friday he intends to vote in the US presidential election, but did not say which candidate he favours.

“I will be voting,” Snowden said, speaking at a conference in Athens by video link from Moscow.

“But as a privacy advocate I think it’s important for me ... that there should never be an obligation for an individual to discuss their vote. And I won’t be doing so with mine.”

He added: “What I will say about the candidates is that I’m disappointed we’re not hearing much about the constitution in this election cycle. We’re not hearing very much about our rights.”

The 33-year-old spoke ahead of the opening of the movie Snowden, starring Joseph Gordon-Levitt.

Snowden thanked human rights groups for their campaign to seek a pardon for him from President Barack Obama.

“I’m not actually asking for a pardon myself because I think the whole point of our system and the foundation of our democracy is a system of checks and balances,” he said. “But ... I’m incredibly grateful and fortunate to be able to experience the support of the world’s three leading human rights organisations.”

A Republican-led bipartisan US House intelligence committee on Thursday released a report calling Snowden a “serial exaggerator and fabricator” who doesn’t fit the profile of a whistle-blower. All of the committee members separately sent Obama a letter urging him not to pardon Snowden, who revealed the NSA’s collection of millions’ of Americans phone records.

The American Civil Liberties Union, Human Rights Watch and Amnesty International are behind the campaign to pardon him.

Kenneth Roth, HRW’s executive director, was on the panel of the Athens conference, and described the effort as “an uphill battle.”

“What we’re hoping is that after the election when Obama is in his final months in office — at that stage he can begin to do something that are appropriate as a matter of conscience but politically difficult,” Roth told journalists.

“One of them we would be is to pardon Snowden,” he said. “There’s been broad recognition that Edward Snowden has done an enormous public service by disclosing the degree to which all of our privacy has been invaded needlessly.”

He hit back at a House Intelligence Committee report that described him as a “disgruntled employee” and not a “principled whistleblower”.

Snowden mocked the committee’s findings on Twitter, challenging several points.

“The claim I ‘doctored performance evaluations?’ This one is amazing: I reported an XSS (hacking) vulnerability in CIA annual review system,” Snowden said.

A summary of the 36-page two-year report, said Snowden “was a disgruntled employee who had frequent conflicts with his managers and was reprimanded just two weeks before he began illegally downloading classified documents”.

The report said Snowden “doctored his performance evaluations” and exaggerated his resume to obtain “new positions at the NSA”.

“He took advantage of its access as network administrator to search hard drives on his colleagues’ computers,” it stated.

According to Snowden, he “could go on”.

“Bottom line: after ‘two years of investigation’, the American people deserve better. This report diminishes the committee,” he said in his concluding tweet.

The report released on September 15, came as Snowden supporters have launched a major push to have him pardoned before US President Barack Obama leaves office, and as Hollywood film “Snowden” hits theatres in the US.

“Edward Snowden is no hero — he’s a traitor who wilfully betrayed his colleagues and his country,” The Telegraph UK quoted Devin Nunes, the Intelligence Committee chairman, as saying.

White House Press Secretary Josh Earnest told the media on September 12 that Snowden is “charged with serious crimes, and it’s the policy of the [Obama] administration that Snowden should return to the US and face those charges”, ABC news reported.

Snowden on September 13, laid out his case for presidential pardon stating that though his actions were against the law, they changed the nation for the better.