United Nations special rapporteur Christof Heyns called on 30 May in Geneva for a worldwide moratorium on what he called "lethal autonomous robotics", or robots that can function autonomously and without involvement of humans.

According to him, these “machines lack morality and mortality, and as a result should not have life and death powers over humans."

Heyns called for the freeze of the robots, now they are not yet being used. This would give nations time to think about the implications of creating them while "the genie is still in the bottle."

However, several states are already working on these devices and a pre-emptive ban is essential, experts say.  "States are working towards greater and greater autonomy in weapons, and the potential is there for such technologies to be developed in the next 10 or 20 years," said Bonnie Docherty of Harvard law school's International Human Rights Clinic.

But technology is evolving quickly and trying to stop it “is a bit like trying to stop time itself,” Heyns explained.

Therefore, in the report to the UN Human Right Council, Heyns highlighted the need of a “moratoria on the production, assembly, transfer, acquisition, deployment and use" of these robots in order to have time to create a global framework for their use.

UN is not the only organisation trying to control the use of “killer robots.” Back in April, an international alliance of NGOs launched the campaign Stop Killer Robots, aiming to ensure that fully autonomous weapons will be banned worldwide.