Fugitive US intelligence whistleblower Edward Snowden was awarded a private literary prize in  Moscow, Russia on Monday.

The US former National Security Agency employee received a commemorative medal from the Zinovyev Institute, a private foundation for the study of creative writings of Russian writer and philosopher Alexander Zinovyev.

"We award the medal to the freest citizen of the world Edward Snowden," RIA Novosti quoted Zinovyev's widow, Olga Zinovyeva, as saying.

Snowden did not appear at the ceremony as he has been keeping low profile since he was granted an asylum in Russia in August 2013.

Zinovyeva described Snowden as a brave man who has demonstrated "citizen's courage and high ethical standards," adding that the institute hopes to hand over the medal to Snowden in person.

Snowden faces three felony charges including espionage after he unveiled a highly classified US intelligence project code-named PRISM.

The United States and Russia have been at odds over Snowden's extradition, with Moscow repeatedly denying the case, citing absence of relevant bilateral agreements.