Billionaire Elon Musk has added his voice to more than 100 tech leaders in a letter to the United Nations warning that "killer robots" could become weapons of terror.
Urging the UN to take action, 116 artificial intelligence leaders and robotics companies from across 26 countries signed the open letter.
Launching the International Joint Conference on Artificial Intelligence (IJCAI), the tech founders state: "Lethal autonomous weapons threaten to become the third revolution in warfare."
Automated tanks, drones and machine guns are among the weapons they fear could lead to an arms race - although the technology does not currently exist.
The memo urges the UN to ban the development and use of such "killer robots" and add them to a list of "morally wrong weapons", which already includes lasers that blind and chemical weapons.
The co-founder of Google's DeepMind - Mustafa Suleyman - also signed the appeal.
The letter says: "Once developed, they will permit armed conflict to be fought at a scale greater than ever, and at timescales faster than humans can comprehend.
"These can be weapons of terror, weapons that despots and terrorists use against innocent populations, and weapons hacked to behave in undesirable ways."
Mr Musk has previously stressed the risk posed by artificial intelligence, recently clashing with Facebook (NasdaqGS: FB - news) founder Mark Zuckerberg , who he claimed had a "limited" understanding of the subject.
Mr Zuckerberg said: "I think people who are naysayers and try to drum up these doomsday scenarios... I just, I don't understand it. It's really negative and in some ways I actually think it is pretty irresponsible."
According the UN's website, a group focused on robot weapons was set to meet on Monday, but the session has been cancelled and rescheduled for November.
Autonomous weapons already being worked on across the world include a fixed-place sentry gun being developed by the South Korean government; an unmanned combat aerial vehicle being developed in the UK by BAE Systems (LSE: BA.L - news) ; robotic tanks being worked on in Russia and the US; and an autonomous warship that was launched in 2016 by the US.