The UK does not have time to solve the problems of online political advertising before the general election, meaning it should be voluntarily suspended by Facebook and Google until after the vote, campaigners, academics and non-profits have said.

In a letter addressed to Mark Zuckerberg and Sundar Pichai, the chief executives of Facebook and Google, as well as Nick Clegg and Kent Walker, the heads of policy of the respective companies, the campaigners write that “with the announcement of the election coming in only six weeks, there is no time for regulations to catch up” with the reality of online advertising.

Q&A How does political advertising work on Facebook? Show Hide In the wake of the Cambridge Analytica scandal, there is a heightened sensitivity around the use of personal data in political campaigning. Facebook allows political parties to target you for adverts in three different ways. They can choose to show ads to people based on age, location, and interests. So, for example, you could choose to advertise to men aged 35-44 in Yorkshire. Or women aged 65+ that Facebook considers to be interested in a specific topic. Additionally, Facebook allows political parties to combine Facebook’s audience with existing data they have, such as phone numbers or email addresses, or people who have been tracked visiting a party’s website. Facebook also has a feature called “Lookalike Audiences”. It allows parties to try to target people who behave similarly on Facebook to those for whom they have contact details. As a result of controversy around political adverts on Facebook, the social media company introduced an Ad Library where you can, in theory, see all the adverts being paid for by political parties, and a rough estimate of how much money has been spent, and the audiences they have been targeting. Martin Belam

“This legislative blackspot is particularly concerning in light of Facebook’s recent policies to allow politicians to openly publish disinformation through ads. Equally concerning is the lack of transparency as to what data is being used to target ads, and how such ads are being targeted,” they say.

“As we prepare to enter purdah, and without proper legislation, we’re calling on you to take a stand and issue an immediate moratorium on all political and issue-based advertising on your platforms until the conclusion of the UK parliamentary elections on 12 December.”

The letter, signed by representatives of seven organisations including Mozilla, Doteveryone, the Open Data Institute and Sheffield University, notes the decision to voluntarily pause political adverts is not without precedent.

“Google blocked political advertising two weeks before polling day,” the letter says. “In the Israeli and Canadian elections, political ads were blocked outright for the duration of the election period.”

Twitter has announced a voluntary suspension of all political adverts, with the chief executive, Jack Dorsey, writing: “It’s not credible for us to say: ‘We’re working hard to stop people from gaming our systems to spread misleading info, but if someone pays us to target and force people to see their political ad … well … they can say whatever they want’.”