Politicians from five countries are demanding that Facebook CEO Mark Zuckerberg appear at a Nov. 27 joint hearing in London after he turned down last week's invitation.
The growing call — which now includes politicians from Australia, Argentina, Ireland, Canada and the UK — is led by Damian Collins, chair of the UK's Digital, Culture, Media and Sport Committee. Collins tweeted the latest letter in response to the social network's rejection early Wednesday.
"We were very disappointed with this dismissive response. As you will see from the list of signatories to this letter, the 'grand committee' on disinformation and fake news is growing," it read.
"Five parliaments are now calling on you to do the right thing by the 170 million users in the countries they represent."
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Leopoldo Moreau of Argentina, James McGrath of Australia and Hildegarde Naughton of Ireland joined Collins and Canada's Bob Zimmer in signing the letter.
"Mark Zuckerberg has set himself the personal challenge of 'fixing' Facebook this year to prevent its misuse in our democratic process," Collins said in an emailed statement. "By being unwilling to face questions about his progress, doubts about his ability to do so remain."
In its letter declining the invitation, Facebook asserted that its senior staff had already appeared before UK and Canadian committees.
"We continue to fully recognize the seriousness of these issues and remain committed to working with you to provide any additional relevant information you require for your respective inquiries," it wrote.
Zuckerberg previously turned down a spring invitation to give evidence to the UK Parliament about Facebook's role in the Cambridge Analytica data scandal, having answered questions before the European Union's Parliament and the US Congress.
On Tuesday, UK Information Commissioner Elizabeth Denham called for Facebook to be subject to stricter regulation and supported Collins' call for Zuckerberg to testify in Britain.
It referred Facebook to Ireland's Data Protection Commission — the lead authority for Facebook under the EU's General Data Protection Regulation — over the way it targets users, in the wake of hitting the social media giant with a £500,000 ($645,000) fine.
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