The ICO's report said other regulatory action would include a criminal prosecution against Cambridge Analytica's parent firm, SCL Elections, for failing to deal with the regulator's enforcement notice. A group of industry executives met with France's President Emmanuel Macron to discuss how to use technology to improve people's lives.
The Facebook probe is part of a wider investigation into the use of data in political campaigns, which the ICO launched past year, the interim results of which are out today.
Sen. Mark Warner, D-Va., the top Democrat on the Senate Intelligence Committee, said in a statement to CNN that Facebook's relationship with Mail.Ru deserved further scrutiny.
The social media giant has said it has since identified 200 other apps which may have been used the same way, and is investigating.
Facebook has been hit with a maximum possible fine for allowing political consulting firm Cambridge Analytica to harvest the information of millions of people without their consent.
Last week Facebook's share price fell after it emerged the Federal Bureau of Investigation had opened its own probe into the scandal. The amount is the maximum that the agency, the Information Commissioner's Office (ICO), can levy for violation of Britain's data-privacy laws.
'People can not have control over their own data if they don't know or understand how it is being used.
"Engagement with the electorate is vital to the democratic process; it is therefore understandable that political campaigns are exploring the potential of advanced data analysis tools to help win votes".
Facebook's chief privacy officer Erin Egan said: 'We should have done more to investigate claims about Cambridge Analytica and take action in 2015.
Collins said Wednesday that the social media giant "should now make the results of their internal investigations known to the ICO, our committee and other relevant investigatory authorities".
Meanwhile, based on entire 2017 revenues of just over $40bn, Facebook would earn £500,000 in just over eight-and-a-half minutes.
The U.K.'s probe adopted a wide lens, focusing not only on Facebook but the ecosystem of players - totaling 172 organizations and 285 individuals - involved in the collection and sale of data about web users for political purposes.