Facebook's founder will face US politicians later about the Cambridge Analytica data scandal.
The social network believes up to 87 million people, including 45 thousand in Ireland, had their information harvested by the political consultancy - through a personality quiz app.
In a written statement before the hearing, Mark Zuckerberg says he "didn't do enough" to protect users’ details.
Yesterday, Mr Zuckerberg met Florida senator Bill Nelson to discuss the issue: