The father of former US spy agency contractor Edward Snowden said on Wednesday he was willing to agree to a request by the FBI to fly to Moscow to see his son, but first needed to know what the security services wanted.

Lonnie Snowden told Russian 24 television the FBI had suggested a "few weeks ago" that he should travel to Moscow to talk to his son, who faces espionage charges in the United States for exposing secret US surveillance programs.

Edward Snowden, whose exposure of the surveillance raised questions about intrusion into private lives, has been stuck in the transit zone of Moscow's Sheremetyevo Airport since arriving from Hong Kong more than a month ago.

His father has had no direct contact with him.

"I received this suggestion (from the FBI to travel to Moscow) a few weeks ago, and I have yet to decline it," Lonnie Snowden said, his English translated into Russian.

He said he believed his 30-year-old son, who has applied for temporary asylum in Russia after the cancellation of his travel documents meant he was unable to travel on to a preferred destination in Latin America, was better off in Moscow.

"If he wants to spend the rest of his life in Russia, I would agree. I am not against it," he said. "If I were in his place, I would stay in Russia, and I hope that Russia will accept him."

Lonnie Snowden again said he did not think his son would get a fair trial in the US because of "what happened in the last 5-6 weeks".

Reuters