The development of robotic weapons or "killer robots" will provide "the capacity of altering irreversibly the nature of warfare, becoming more detached from human agency, putting in question the humanity of our societies," Archbishop Ivan Jurkovic told a group of experts at the United Nations in Geneva.

The archbishop, who is the Vatican observer to U.N. agencies in Geneva, spoke Nov. 22 at a meeting of the high contracting parties to the Convention on Prohibitions or Restrictions on the Use of Certain Conventional Weapons Which May Be Deemed to Be Excessively Injurious or to Have Indiscriminate Effects, held in Geneva Nov. 21-23. The Vatican mission in Geneva released the archbishop's remarks Nov. 27.

The legal and ethical implications of Lethal Autonomous Weapons Systems (LAWS) have been discussed and on the convention's agenda for the past five years, the archbishop said in his speech.

The International Committee of the Red Cross has defined LAWS as being "any weapon system with autonomy in its critical functions. That is, a weapon system that can select -- i.e. search for or detect, identify, track, select -- and attack -- i.e. use force against, neutralize, damage or destroy -- targets without human intervention."

The first such autonomous weapon was the land mine, but rapid advances in artificial intelligence and machine learning have broadened the potential for weapons with extensive autonomy from human decision-making.

"The Holy See has expressed its concerns on several occasions" about this deadly form of weapons system, the archbishop said.

"Various proposals for possible concrete outcomes have been put forward; what these proposals have in common is the underlying need for a multilateral approach and the need to retain the human person at the heart of decisions exerting injurious or lethal force," he said.

The Vatican advocates the attitudes of precaution and prevention as being "the only options that will ensure a sound and lasting outcome."

"In order to prevent an arms race and the increase of inequalities and instability, it is an imperative duty to act promptly: Now is the time to prevent LAWS from becoming the reality of tomorrow’s warfare," he said.

The convention's parties "should make a courageous and enlightened decision of prohibiting LAWS like it did in the past concerning other types of weapons," Archbishop Jurkovic said, like with the international ban on land mines and the nuclear nonproliferation treaty.