The ICO is investigating the way in which Facebook data was acquired and used by the company. The move, which is part of a wider ICO investigation on the use of data analytics for political purposes, follows a report published by the Observer on Saturday ( 17 March) in which a whistleblower alleged that Cambridge Analytica had harvested millions of Facebook user profiles. 

In a statement issued by the ICO, information commissioner Elizabeth Denham said: "On 7 March, my office issued a Demand for Access to records and data in the hands of Cambridge Analytica. Cambridge Analytica has not responded by the deadline provided; therefore, we are seeking a warrant to obtain information and access to systems and evidence related to our investigation."

Facebook has agreed to stop its own search of Cambridge Analytica’s premises, at the ICO’s request. Denham said: "Such a search would potentially compromise a regulatory investigation."

Denham said: "It is important that the public are fully aware of how information is used and shared in modern political campaigns and the potential impact on their privacy. We are continuing to invoke all of our powers and are pursuing a number of live lines of inquiry. Any criminal and civil enforcement actions arising from the investigation will be pursued vigorously."

The head of the European Parliament said on Monday ( 19 March) that it would investigate whether the data of Facebook users has been misused.