A group including conservative US commentator Steve Bannon, Prince Harry and Apple co-founder Steve Wozniak has signed a statement calling for a ban on developing superintelligent artificial intelligence until the public demands it and science paves a safe way forward. The letter, by a politically and geographically diverse group of public figures, is squarely aimed at tech giants like Google, OpenAI and Meta Platforms that are racing each other to build a form of artificial intelligence designed to surpass humans at many tasks. "We call for a prohibition on the development of superintelligence, not lifted before there is broad scientific consensus that it will be done safely and controllably, and strong public buy-in," says the statement, signed by prominent computer scientists, economists, artists, evangelical Christian leaders and American conservative commentators. In a preamble, the letter notes that AI tools may bring health and prosperity, but alongside those tools, "many leading AI companies have the stated goal of building superintelligence in the coming decade that can significantly outperform all humans on essentially all cognitive tasks.  "This has raised concerns, ranging from human economic obsolescence and disempowerment, losses of freedom, civil liberties, dignity, and control, to national security risks and even potential human extinction." Prince Harry added in a personal note that "the future of AI should serve humanity, not replace it. I believe the true test of progress will be not how fast we move, but how wisely we steer. There is no second chance." Signing alongside the Duke of Sussex was his wife Meghan, the Duchess of Sussex. "This is not a ban or even a moratorium in the usual sense," wrote another signatory, Stuart Russell, an AI pioneer and computer science professor at the University of California, Berkeley.  "It's simply a proposal to require adequate safety measures for a technology that, according to its developers, has a significant chance to cause human extinction. Is that too much to ask?" Also signing were AI pioneers Yoshua Bengio and Geoffrey Hinton, co-winners of the Turing Award, computer science's top prize.  Hinton also won a Nobel Prize in physics in 2024. Both have been vocal in bringing attention to the dangers of a technology they helped create.  But the list also has some surprises, including Bannon and fellow conservative commentator Glenn Beck, in an attempt by the letter's organisers at the nonprofit Future of Life Institute to appeal to US President Donald Trump's Make America Great Again movement. Also on the list are Apple co-founder Steve Wozniak; British billionaire Richard Branson; the former chairman of the US Joint Chiefs of Staff Mike Mullen; and Democratic foreign policy expert Susan Rice, who was national security adviser to former US president Barack Obama.  Former Irish president Mary Robinson and several British and European parliamentarians signed, as did actors Stephen Fry and Joseph Gordon-Levitt, and musician will.i.am, who has otherwise embraced AI in music creation. With Reuters Australian Associated Press