“The very worst people on the internet are obviously quite excited about the opportunities of Elon Musk’s Twitter,” said Sunder Katwala, the director of independent think tank British Future.

Mr Katwala has been working with the volunteer network since he was targeted by a Twitter troll who had previously been banned for racist abuse targeting England footballers…

Mr Katwala said that, by effectively pledging “if it’s legal it’s on”, Twitter under Mr Musk might run into challenges with how it handles content in jurisdictions outside of the US. Holocaust denial, for instance, is illegal in Germany but not in the US – although it is socially unacceptable.

Joe Mulhall, director of research at anti-fascism and anti-racism campaign group Hope Not Hate, told PA the mood among the far right is “hugely” concerning.