One hundred and sixteen roboticists and AI researchers, including SpaceX founder Elon Musk and Google Deepmind co-founder Mustafa Suleyman, have signed a letter to the United Nations calling for strict oversight of autonomous weapons, a.k.a. “killer robots.” Though the letter itself is more circumspect, an accompanying press release says the group wants “a ban on their use internationally.”

Other signatories of the letter include executives and founders from Denmark’s Universal Robotics, Canada’s Element AI, and France’s Aldebaran Robotics.

The letter describes the risks of robotic weaponry in dire terms, and says that the need for strong action is urgent. It is aimed at a group of UN officials considering adding robotic weapons to the UN’s Convention on Certain Conventional Weapons. Dating back to 1981, the Convention and parallel treaties currently restrict chemical weapons, blinding laser weapons, mines, and other weapons deemed to cause “unnecessary or unjustifiable suffering to combatants or to affect civilians indiscriminately.”

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Robotic warriors could arguably reduce casualties among human soldiers – at least, those of the wealthiest and most advanced nations. But the risk to civilians is the headline concern of Musk and Suleyman’s group, who write that “these can be weapons of terror, weapons that despots and terrorists use against innocent populations, and weapons hacked to behave in undesirable ways.”

The letter also warns that failure to act swiftly will lead to an “arms race” towards killer robots – but that’s arguably already underway. Autonomous weapons systems or precursor technologies are available or under development from firms including Raytheon, Dassault, MiG, and BAE Systems.

Element AI founder Yoshua Bengio had another intriguing warning – that weaponizing AI could actually “hurt the further development of AI’s good applications.” That’s precisely the scenario foreseen in Frank Herbert’s sci-fi novel Dune, set in a universe where all thinking machines are banned because of their role in past wars.

The UN weapons group was due to meet on Monday, August 21, but that meeting has reportedly been delayed until November.