Big tech congress hearing - live: Facebook's Zuckerberg defends Twitter's decision to ban Trump Jr over 'harmful' coronavirus post

Facebook CEO Mark Zuckerberg testifies before a joint hearing of the US Senate Commerce, Science and Transportation Committee and Senate Judiciary Committee on Capitol Hill, April 10, 2018 in Washington, DC: JIM WATSON/AFP via Getty Images
Facebook CEO Mark Zuckerberg testifies before a joint hearing of the US Senate Commerce, Science and Transportation Committee and Senate Judiciary Committee on Capitol Hill, April 10, 2018 in Washington, DC: JIM WATSON/AFP via Getty Images

Representatives of the biggest tech companies in the world are to be grilled by politicians amid increasing concern over their effect on society.

Apple's Tim Cook, Amazon's Jeff Bezos, Facebook's Mark Zuckerberg and Google's Sundar Pichai will all face US lawmakers who will ask questions on a variety of issues.

They are likely to include antitrust concerns, relating to questions of whether the companies have abused their dominance to push their own products, as well as ongoing worries about censorship and free speech on social media platforms.

The CEOs are expected to argue that their platforms are still not as dominant as might be assumed, and that they face threats from other markets such as China, which could become more powerful if they were subject to limiting regulation.

The hearings begin at 12pm local eastern time, or 5pm in the UK. Attendees will be questioned virtually, in keeping with coronavirus restrictions.

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