The spokesperson said: "In particular, we believe that the updated policy does not provide sufficient information to enable UK users of Google's services to understand how their data will be used across all of the company's products.
Google moved to change a number of service usage policies last year. The ICO can fine Google up to £500,000 for breaches of the UK Data Protection Act.
The ICO recently threatened other action against Google if it didn't destroy Street View WiFi data it holds by 25 July.
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