Washington: Facebook Inc. chief executive officer Mark Zuckerberg will appear before a joint hearing of the Senate Judiciary and Commerce Committees next Tuesday, the chairmen of those panels said on Wednesday night.

“Our joint hearing will be a public conversation with the CEO of this powerful and influential company about his vision for addressing problems that have generated significant concern about Facebook’s role in our democracy, bad actors using the platform, and user privacy," the Commerce Committee chairman, Senator John Thune of South Dakota, said in a statement.

Zuckerberg had already agreed to appear before the House Energy and Commerce Committee on Wednesday, 11 April, the chairman and top Democrat on that committee announced on Wednesday.

“This hearing will be an important opportunity to shed light on critical consumer data privacy issues and help all Americans better understand what happens to their personal information online," said chairman Greg Walden of Oregon, in a joint statement with ranking panel Democrat Frank Pallone of New Jersey.

The announcements came on the same day that Facebook reported that data on as many as 87 million people, most of them in the US, may have been improperly shared with the research firm Cambridge Analytica, which worked on Donald Trump’s 2016 campaign.

This was Facebook’s first official confirmation of the possible scope of the data leak, which was previously estimated at roughly 50 million.

The company also said that data on most of its 2 billion users could have been accessed improperly.

Conference call

“We didn’t take a broad enough view of what our responsibility was and that was a huge mistake. It was my mistake," Zuckerberg, Facebook’s co-founder as well as chairman, said in a Wednesday afternoon conference call with reporters. “We’re broadening our view of our responsibility."

Other congressional committees are looking to hear from Facebook executives too. Senate Judiciary Committee staff members didn’t immediately respond to Wednesday to whether Zuckerberg has agreed to a date to appear before that panel.

Zuckerberg has faced intense criticism from lawmakers in both parties after reports that Cambridge Analytica harvested data from millions of Facebook users without their knowledge.

He never testified before Congress, but decided last week that he would need to do so now, according to a person familiar with the matter.

The company also faces continued scrutiny over its failure to prevent exploitation of its network by Russians using fake news and fake accounts.

The Federal Trade Commission has opened an investigation into Facebook’s privacy policies.

Zuckerberg has written Facebook posts and done several news interviews — a rare move for him — promising to do better in the future, but a hearing where he’ll be grilled by lawmakers raises the stakes considerably.

Lower-level Facebook executives have briefed staff behind closed doors but lawmakers have complained they couldn’t answer all of their questions.

Public hearings last year on Russian use of social media featured top lawyers from Facebook, Twitter Inc. and Alphabet Inc.’s Google but they, too, failed to satisfy a number of senators. The lawmakers said CEOs and decision-makers, not their lawyers, should be held to account for letting their networks be abused and for saying what they will do to prevent a recurrence.