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