Mozilla and Commerzbank pull advertising from Facebook over Cambridge Analytica data breach

US software giant and German bank 'press pause' on ties to social network

US software giant Mozilla and Germany's Commerzbank have both said they will pull advertising from Facebook over the Cambridge Analytica affair.

The social network has been under fire all week over revelations that the political consultancy harvested private data from the Facebook profiles of 50m Americans and handed it on to the Donald Trump campaign for use in the micro-targeting of swing voters during the 2016 US presidential election.

Facebook CEO Mark Zuckerberg has since apologised and volunteered to testify before Congress, conceding: "We made mistakes".

Chief operating officer Sheryl Sandberg said the site would be "open to regulation" as it seeks to rebuild public trust over the handling of users' information and accusations that Russian bots were engaged in the spread of "fake news" and misinformation across its pages in a bid to sway the race for the White House.

Writing in a blog post, Mozilla CEO Denelle Dixon said the company was "pressing pause" on its Facebook advertising.

"This news caused us to take a closer look at Facebook’s current default privacy settings given that we support the platform with our advertising dollars," she wrote.

"While we believe there is still more to learn, we found that its current default settings leave access open to a lot of data - particularly with respect to settings for third party apps.

"We are encouraged that Mark Zuckerberg has promised to improve the privacy settings and make them more protective.

"When Facebook takes stronger action in how it shares customer data, specifically strengthening its default privacy settings for third party apps, we’ll consider returning."

Commerzbank, Germany's second-largest lender, quickly followed Mozilla's example.

"We are pausing our campaign on Facebook. Brand safety and data security are very important to us," said Uwe Hellmann, the bank's brand strategy chief.

Yesterday the UK's advertising industry trade body ISBA, which represents more than 3,000 brands, told Facebook "enough is enough" and demanded to know more about the potential ramifications of the recent data breach.

“We want reassurances for our members that [Facebook] will get to the bottom of the issues and any implications for the public and for advertisers," said ISBA director general Phil Smith.