Edward Snowden: White House Rejects Pardon Plea

President Obama has rejected calls to pardon Edward Snowden for revealing details of America's unlawful spying programme.

A petition on the White House website declaring the former National Security Agency employee a national hero has gathered 167,955 signatures in two years.

But Obama's advisor on Homeland Security and Counterterrorism has spoken-out to insist Snowden should return to the US from Russia to face a criminal trial for espionage.

"Mr Snowden's dangerous decision to steal and disclose classified information had severe consequences for the security of our country and the people who work to protect it," said Lisa Monaco.

"He should come home to the United States and be judged by a jury of his peers, not hide behind the cover of an authoritarian regime.

"Right now, he's running away from the consequences of his actions."

Snowden, 32, sought refuge in Russia after leaking classified details of joint US and UK spying programmes to journalists.

In May, the US court of appeal ruled that government bulk collection of the telephone metadata of millions of innocent citizens was unlawful.

UK security chiefs recently warned that Snowden's actions compromised anti-terror activity , with former GCHQ director Sir David Omand describing it as a "huge, strategic setback" for the West.

But journalist Glenn Greenwald criticised the claims, saying unnamed government officials quoted by The Sunday Times were "cowards" for not putting their names to the accusations.

Mr Greenwald - who co-operated with Snowden over the leaks - called the story "shoddy" journalism.

"There's no way to get at the people who are making the claims because they're hiding behind the journalists, and there's no evidence to analyse or dissect because none is offered," he told Sky News.