Snowden to leave Russia when opportunity emerges: Putin

American whistleblower Edward Snowden will leave Russia when the opportunity emerges, Russian President Vladimir Putin has said.

"He has arrived in our territory without invitation, he didn't fly to us, he arrived as a transit passenger to other countries," Xinhua quoted Putin as saying during a meeting with students in Leningrad region.

The president said Snowden was blocked from further travel after Washington revoked the 29-year-old whistleblower's passport.

"They (the US authorities) scared off all other countries, so no one wants to accept him (Snowden). So, in effect, they've blocked him on our territory themselves," Putin said.

The president declined to comment on Snowden's future, saying: "How can I know that? This is his life and his fate."

But he added: "Eventually, he (Snowden) wants to move to a permanent residence in another territory."

"As soon as the opportunity appears to move somewhere, he of course will do that," Putin said.

Putin also made it clear that Moscow is not going to harm its relations with the US, and that Snowden could only continue with his human rights activities "without our involvement".

Snowden met Russian human rights activists and lawyers at Moscow's Sheremetyevo International Airport last week.