Leaders are being urged to take a first step towards banning "killer robot" weapons that think for themselves later this week.
Nations will vote on whether to consider the move at the annual meeting of the Convention on Conventional Weapons (CCW) taking place in Geneva on Friday after France, which will chair the meeting, proposed a mandate to add fully autonomous weapons to the Convention's work programme next year.
The organisation Campaign to Stop Killer Robots is urging the international community to back the mandate, which could lead to a global agreement not to develop fully autonomous drones that select and engage targets without human intervention.
"Governments should begin to act now to ensure that human control over targeting and attack decisions is never relinquished to machines in the future," said Steve Goose, from Human Rights Watch, a co-founder of the Campaign.
"Nations need to start working urgently on both national prohibitions and an international ban on these fully autonomous weapons."
Fully independent functioning weapons do not yet exist but drones operated by the US, UK, Israel and South Korea, already have some degree of autonomy and lethality.
Some militarily hi-tech countries, such as China and Russia, are believed to be moving towards systems that would leave combat decisions to machines, say campaigners.
While sci-fi scare stories of machines wiping out the human race, as explored in the Terminator films, seem farfetched Goose and his colleagues believe the dangers of releasing human control over "intelligent" weapon systems are very real.
The Campaign to Stop Killer Robots is an international coalition of 44 non-governmental organisations in 21 countries that was launched in London in April this year with a mission to see the international community put in place a comprehensive ban on fully autonomous weapons that can kill and destroy without human commands.
"Governments must address the fundamental question of whether it is inherently wrong to let autonomous machines make programmed decisions about who and when to kill," said Professor Noel Sharkey, chair of the International Committee for Robot Arms Control (ICRAC), another campaign founder.
"It is possible to prevent the development and proliferation of autonomous robot weapons, but only if we act now before there is too much investment."
He points to the example set in 1995 when CCW member states agreed on a protocol banning blinding lasers.
Last month the ICRAC released a statement endorsed by 272 engineers, computing and artificial intelligence experts in 37 countries calling for a ban on the development and deployment of weapon systems that take their own decisions to apply violent force.
Representatives from the Campaign to Stop Killer Robots presented their concerns at an event at the United Nations in Geneva.
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