It’s been reported (WSJ) that an internal report by the UK’s privacy regulator, the Information Commissioner’s Office (ICO), has said that Google’s proposed replacements for cookies fall short in terms of protecting consumer privacy.

The ICO’s draft report reportedly says that Google’s proposed technology, known as the ‘Privacy Sandbox,’ leaves gaps that could be exploited by advertisers, potentially undermining privacy and identifying users who should be kept anonymous.

The WSJ reports that the ICO now wants Google to make changes and share its concerns with UK’s competition regulator, the Competition and Markets Authority (CMA).