The father of US intelligence leaker Edward Snowden has held an "emotional" meeting with his son for the first time since the fugitive took refuge in Russia to escape US justice, a report said Friday.

Lon Snowden met his son after arriving in Moscow from the United States on Thursday, a source familiar with the situation told the Interfax news agency, without specifying the time or place of the meeting.

"The meeting has already taken place. It was very emotional," the source told the agency, saying further details would not be given for security reasons.

Russia has granted Edward Snowden one year temporary asylum but the United States wants him to be extradited to face charges over his leaking of sensational details of US surveillance programmes.

The former National Security Agency (NSA) contractor spent over a month in transit at a Moscow airport before being granted asylum. Since then his whereabouts have been a mystery.