Former US intelligence contractor Edward Snowden, who leaked extensive US intelligence surveillance operations, has been granted Russian citizenship.
The decree was signed by Russian President Vladimir Putin on Monday.
Mr Snowden, 39, has been living in exile in Russia since exposing the National Security Agency (NSA) programme affecting millions of Americans in 2013.
Mr Snowden, who faces espionage charges in the US, has made no public comments.
Mr Snowden said afterwards that he felt vindicated by the ruling.
Top US intelligence officials had publicly insisted the NSA had never knowingly collected data from private phone records, until Mr Snowden exposed evidence to the contrary.
Following the revelation, officials said the NSA's surveillance program had played a crucial role in fighting domestic terrorism, including the convictions of Basaaly Saeed Moalin, Ahmed Nasir Taalil Mohamud, Mohamed Mohamud, and Issa Doreh, of San Diego, for providing aid to al-Shabab militants in Somalia.
Mr Snowden's lawyer Anatoliy Kucherena was on Monday quoted by Russian state-run news agencies as saying that his client has never served in the Russian army, and therefore would not be called up as part of a partial mobilisation announced by President Putin last week.
The Russian authorities say they want to enlist 300,000 army reservists to fight in Ukraine, amid growing public opposition.
Reports in opposition Russian media suggest that up to one million people could be called up.