Fugitive US intelligence leaker Edward Snowden on Monday accused US President Barack Obama of "pressuring the leaders" of countries from which he has sought protection.

In his first public announcement since fleeing Hong Kong eight days ago, he accused Obama of ordering his Vice President Joe Biden to put pressure on leaders of countries where he was seeking asylum.

"On Thursday, President Obama declared before the world that he would not permit any diplomatic 'wheeling and dealing' over my case," Snowden said in statement issued to the WikiLeaks site.

"Yet now it is being reported that after promising not to do so, the President ordered his Vice President to pressure the leaders of nations from which I have requested protection to deny my asylum petitions," he added.

Ecuador's President Rafael Correa has said Biden raised the issue of Snowden in a conversation over the weekend, asking him to reject the fugitive computer analyst's asylum request.

Snowden, in his statement issued from his refuge at Moscow's Sheremetyevo airport, said Obama was guilty of "deception" and imposing "the extralegal penalty of exile.

"These are the old, bad tools of political aggression," he continued.

"Their purpose is to frighten, not me, but those who would come after me."

The Obama administration had rejected the US Universal Declaration of Human Rights and had chosen "the strategy of using citizenship as a weapon," he said.

"Although I am convicted of nothing, it has unilaterally revoked my passport, leaving me a stateless person," he added.

"Without any judicial order, the administration now seeks to stop me exercising a basic right. A right that belongs to everybody. The right to seek asylum."

Snowden has applied for asylum in Russia and President Vladimir Putin said on Monday he was welcome to stay as long as he stopped leaking US intelligence reports.

The former CIA operative revealed that he left Hong Kong "after it became clear that my freedom and safety were under threat".

"In the end the Obama administration is not afraid of whistleblowers like me," he explained. "We are stateless, imprisoned, or powerless.

"No, the Obama administration is afraid of you. It is afraid of an informed, angry public demanding the constitutional government it was promised - and it should be," said Snowden.

He concluded: "I am unbowed in my convictions and impressed at the efforts taken by so many."