Joseph Gordon-Levitt is a supporter of Edward Snowden.

The 34-year-old actor stars as the former National Security Agency contractor, who released classified documents to the media in 2013, in the new Oliver Stone-directed biopic.

And while debate continues to rage about the rights and wrongs of Snowden's actions, the Hollywood star is unambiguous in his stance.

Reflecting on his four-hour conversation with Snowden, Joseph said: ''I left knowing without a doubt that what [Snowden] did, he did because he believed it was the right thing to do, that he believed it would help the country he loves.

''Now, as he would say, it's not for him to say whether it was right or wrong. That's really for people to decide on their own, and I would encourage anybody to decide that on their own. I don't want to be the actor guy who's like, 'You should listen to me! What he did was right!'

''I don't think that's my place. Even though that is what I believe - that what he did was right.''

Joseph is also set to star as Philippe Petit, who walked on a wire between the Twin Towers of the World Trade Center in 1974, in 'The Walk' - and he sees striking similarities between the two.

He told the Guardian newspaper: ''What I found was someone warm, kind, thoughtful: a lot like Philippe. Both of them are incredibly driven towards something they believe in.''