European data protection authorities have for the first time threatened to fine Google, if the Silicon Valley-based company does not address their privacy concerns within three months.

The co-ordinated move by regulators in Britain, Germany, France, Italy, Spain and the Netherlands could result in Google having to pay several million euros, under proposed rules.

"Time is running out for Google to get serious about data protection," Viviane Reding, the EU's top justice official in charge of bolstering the bloc's data protection rules, said on Twitter.

The decision to threaten Google with sanctions comes eight months after a probe led by EU regulators concluded that the US internet company failed properly to disclose how it was using its users’ personal data across multiple platforms.

It also comes amid growing concern about the extent to which both governments and private companies collect and exploit people’s personal data on a vast scale.

European regulators can impose limited fines for the time being, but a new data protection regulation that may be adopted later this year would give them the power to impose monetary sanctions worth up to 2 per cent of a company’s annual global turnover. Google had $50bn in revenues last year.

Google has also been criticised by regulators for merging its privacy rules for different online services. Under this arrangement, once a user agrees to the privacy rules for one Google service, these terms automatically apply to other services.

"Our privacy policy respects European law and allows us to create simpler, more effective services," said Al Verney, a spokesman for Google in Brussels. "We have engaged fully with the data protection authorities involved throughout this process and will continue to do so going forward."

(c) 2013 The Financial Times Limited