Russia on Wednesday condemned a British crackdown on the Guardian newspaper over its publication of US security secrets leaked by Edward Snowden, accusing London of double standards.

Russia on Wednesday condemned a British crackdown on the Guardian newspaper over its publication of US security secrets leaked by Edward Snowden, accusing London of double standards.

"The steps undertaken by the British authorities towards the Guardian newspaper are out of synch with the British side's stated commitment to universal human rights standards including freedom of the press," the foreign ministry said.

"This once more speaks of the perverse practice of double standards applied by London in the field of human rights."

The Guardian said this week that the British government had forced it to destroy files or face a court battle over its publication of US security secrets leaked by former US National Security Agency contractor Snowden, who has been granted temporary asylum in Russia.

The revelation came as Britain faced sharp criticism for detaining the partner of US journalist Glenn Greenwald -- who has written extensively about Snowden's revelations for the Guardian -- for  nine hours at a London airport on Sunday.

The Russian foreign ministry's statement defended Snowden, saying he had exposed "crude violations of international law directly concerning the rights of millions of people in the world."