Google urged to change privacy rules by data regulators
It follows changes to the policy two years ago which regulators felt breached European rules.
Among other things, it says Google must tell users exactly what data is collected and with whom it is shared.
The dispute has been running since March 2012 when Google consolidated its 60 privacy policies into one and started combining data from YouTube, Gmail and Google Maps.
Users were given no means to opt out of the changes.
Although Google has not been directly accused of acting illegally, it has been accused of providing "incomplete and approximate" details raising "deep concerns about data protection and the respect of the European law".
"It has made some changes but our investigation won't end until we believe it is fully compliant," said a spokesman for the UK's information commissioner's office (ICO).
In a letter addressed to Google's chief executive Larry Page, the European Union's data protection working party wrote: "Google must meet its obligations with respect to the European and national data protection legal frameworks and has to determine the means to achieve these legal requirements."
A spokesman for Google told the Reuters news agency that it was looking forward to discussing the new guidelines.
"We have worked with different data protection authorities across Europe to explain our privacy policies," he said.
Regulators in Italy, France, Spain, Germany, Britain and the Netherlands have launched investigations into Google's privacy policies and, in January, France fined Google 150,000 euros (£117,000) for failure to comply with its privacy rules.
"It is disappointing that two years of deliberation has led to the preparation of a document that is the equivalent of selling cucumbers to the gardener," said Anna Fielder, chairwoman of trustees at campaign group Privacy International.
"The guidelines are fundamental basics that Google should have implemented years ago, and the weakness of the language used in framing this will mean Google will do nothing to comply.
"These guidelines are doing nothing more than stating the obvious, and it is shameful that it took the Article 29 Working Party two years to come up with something that Google should already have been complying with," she said.