Fugitive US whistleblower Edward Snowden has to live a strictly covert life in Russia due to personal safety concerns, said his Russian lawyer on Tuesday.

The situation surrounding Snowden "has not been calm" and he lives under permanent protection, said Anatoly Kucherena, claiming that he and his client are under constant surveillance.

"To be honest, I don't know who these people (following us) were, it's hard to tell. It could have been journalists. I don't want to make accusations," the RIA Novosti news agency quoted Kucherena as saying.

The remarks were made during the presentation of Kucherena's documentary novel "Time of the Octopus," a fictionalized version of Snowden's saga, to be published in trilogy, with its copyright sold to US director Oliver Stone last year.

Still, the lawyer added, the former US National Security Agency's contractor tries to live a more or less normal life -- visiting theaters and supermarkets or travelling in Russia.

"He's a free man," Kucherena said, noting that despite his gradual adaptation to the life in Russia, Snowden is craving to go back home.

"We're doing everything possible to solve this issue (of his return to the US)," said the lawyer.

He also said that Snowden has been avoiding talking to the Russian media directly for fear that his words could be misinterpreted.

"He isn't going to slam the United States here on the territory of the Russian Federation," said Kucherena.

Snowden faces three felony charges in the United States, including espionage, after he disclosed a classified US intelligence project code-named PRISM.

He has got a refugee status in Russia since August 2013 and currently holds a Russian residential permit valid for three years. But the status will be canceled once Snowden leaves Russia.

The US and Russia have been at odds over Snowden's extradition, which Moscow has repeatedly resisted citing the absence of relevant bilateral agreements.