Facebook chief operating officer Sheryl Sandberg and Twitter chief executive Jack Dorsey will attend a hearing before the Senate Intelligence Committee on 5 September to give evidence in a hearing on social media firms’ responses to Russian interference in US elections.
Google’s chief executive Sundar Pichai and its parent company Alphabet’s chief executive Larry Page were also invited to testify, however Google declined the request
Dorsey will then go on to appear before the House energy and commerce committee as the sole witness in a hearing, investigating allegations from Conservative politicians that Twitter algorithms unfairly target right-wing politicians, viewpoints and media outlets.
This comes as US President Donald Trump last week launched a vendetta against Google, claiming it rigged search results in favour of negative stories about him from “leftwing media”.
Read more: Trump doubles down on US tech giants attack
Trump also tweeted a video reportedly showing Google's failure to promote his last State of the Union address on its homepage, despite promoting all of former President Barack Obama's addresses since 2012.
Google later denied the video's accuracy, with Google Lab director Steve Grove pointing to evidence on popular web archive site Wayback Machine which showed Google had indeed promoted Trump's address.
The attack was later followed up by UK foreign minister Jeremy Hunt, who lashed out at Google over allegedly failing to cooperate with government efforts to crack down on child abuse content online.
Google again denied these claims, saying it had tried to send a policy expert to the Five Eyes conference at policymakers' requests.