The company blamed the “siege of media coverage” which it said was “unfairly negative” for driving away virtually all of its customers and suppliers and insisted that its employees had “always acted ethically and lawfully”.

In the US, bankruptcy proceedings will start for Cambridge Analytica LLC and some of the company’s US affiliates in the US Bankruptcy Court for the Southern District of New York.

Cambridge Analytica has ceased all operations with immediate effect and accountancy firm Crowe Clark Whitehill has been appointed to act as its insolvency administrator.

In a statement Cambridge Analytica said: “Over the past several months, Cambridge Analytica has been the subject of numerous unfounded accusations and, despite the company’s efforts to correct the record, has been vilified for activities that are not only legal, but also widely accepted as a standard component of online advertising in both the political and commercial arenas.”

It added that because of the accusations levelled at it, Queen’s Counsel Julian Malins had conducted an independent investigation into the allegations about its political activities.  

Malins’ full report concluded with him saying: “I have investigated and dealt in this report with a number of serious allegations against both SCL and CA. It has to be recorded and [Alexander] Nix accepts, that some of the fuel and several of the sparks, which have ignited the fire which has engulfed SCL and CA and kept it burning, were provided by him and [Mark] Turnbull. However, I have not found those allegations to have been borne out by the facts.”

As the news of Cambridge Analytica closure broke, Damian Collins, chair of the parliamentary Digital, Culture, Media and Sport (DCMS) Committee tweeted: “Cambridge Analytica and SCL group cannot be allowed to delete their data history by closing. The investigations into their work are vital.”

The Information Commissioner’s Office said in a statement: "The ICO has been investigating the SCL Group and Cambridge Analytica as part of a wider investigation into the use of personal data and analytics by political campaigns, social media companies and others. We will be examining closely the details of the announcements of the winding down of Cambridge Analytica and the status of its parent company.

"The ICO will continue its civil and criminal investigations and will seek to pursue individuals and directors, as appropriate and necessary even where companies may no longer be operating. We will also monitor closely any successor companies using our powers to audit and inspect, to ensure the public is safeguarded."

And it may not be all over as The Guardian reported that the team behind Cambridge Analytica had set up a new company called Emerdata, with Alexander Nix listed as a director. Among its other directors are SCL Group executives and the daughter of billionaire Trump-backer and Cambridge Analytica investor Robert Mercer.