Google's proposed privacy changes have been branded unlawful by a French data protection organisation leading the European investigation into changes that are set to come into effect from 1 March.
Isabelle Falque-Pierrotin from the Commission Nationale de L'informatique et Des Libertes (CNIL), which is leading the Article 29 Working Party's investigation into Google's changes, said that it does not believe they conform to European laws.
"Our preliminary analysis shows that Google's new policy does not meet requirements of the European Directive on Data Protection, especially regarding the information provided to data subjects," she said in the letter.
"The CNIL and the EU data protection authorities are deeply concerned about the combination of personal data across services: they have strong doubts about the lawfulness and fairness of such proceedings."
The organisation urged Google to "pause" its plan to implement these changes and instead let more work be carried out on the implications for users' privacy.
But Google dismissed the concerns, claiming it had managed to reach a solution that it believes address data protection rules.
"Over the past month we have offered to meet with the CNIL on several occasions to answer any questions they might have, and that offer remains open," it said.
"We believe we've found a reasonable balance between the Working Party's recommendations: to ‘streamline and simplify' our policies while providing ‘comprehensive information' to users."
Despite Google's claims, the letter is just the latest in a long-line of high-profile organisation that have expressed concerns over its proposed changes, along with several US senators.
Rivals have also used the changes to attack Google, with Microsoft taking out adverts trying to tempt users concerned with the changes to switch to its services.
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