Facebook has admitted that it tasked it a public relations firm to focus public attention on Google’s privacy practices.

The social network admitted hiring Burson-Marsteller to draw press attention to privacy implications of Google’s Social Circles, one of the search giant’s lower profile offerings, but one which challenges Facebook directly.

"We wanted third parties to verify that people did not approve of the collection and use of information from their accounts on Facebook and other services for inclusion in Google Social Circles," Facebook said in a statement.

The intention had been to "focus attention on this issue, using publicly available information that could be independently verified by any media organisation or analyst".

The company denied that it had lead a ‘smear’ campaign against Google.

When discussing the issues with journalists, Burson-Marsteller did not reveal that it was being employed by Facebook. The firm told Sky News that Facebook "requested that its name be withheld on the grounds that it was merely asking to bring publicly available information to light and such information could then be independently and easily replicated by any media."

Google Social Circle is a service that calculates users’ social connections, by analysing data that allegedly includes their Facebook friends.

Both Facebook and Google come under regular criticism from privacy rights and data protection advocacy groups. Only this week, security firm Symantec revealed that Facebook applications have been leaking users’ private data for years. Google, meanwhile, been accused of breaching privacy with projects like navigation service Google Streetview.