Pope Francis called Friday for a ban on "lethal autonomous weapons", as he became the first pontiff to address the G7 with a speech on the perils of artificial intelligence.
"In light of the tragedy that is armed conflict, it is urgent to reconsider the development and use of devices like the so-called 'lethal autonomous weapons' and ultimately ban their use," the 87-year-old said.
"This starts from an effective and concrete commitment to introduce ever greater and proper human control. No machine should ever choose to take the life of a human being," he told the meeting in Puglia, southern Italy.
Francis, invited by Italian Prime Minister Giorgia Meloni to address the Group of Seven summit, has repeatedly denounced the arms industry and those he says profit from wars and death.
AI is already being used on the battlefield and its move into modern warfare is raising concerns about the risks of escalation and the role of humans in decision making.
AI has shown itself to be faster but not necessarily safer or more ethical, and the development of weapons systems that could kill without human intervention poses ethical and legal challenges.
"Artificial intelligence (is) at the same time an exciting and fearsome tool," Francis told leaders gathered at the luxury Borgo Egnazia resort.
"We would condemn humanity to a future without hope if we took away people's ability to make decisions about themselves and their lives, by dooming them to depend on the choices of machines," he warned.
'Crucial role'
The G7, which brings together Britain, Canada, France, Germany, Italy, Japan and the United States, said on Friday that AI "can play a crucial role in promoting progress and development in our societies".
"We recognise the impact of AI on the military domain and the need for a framework for responsible development and use," the leaders said in a draft statement seen by AFP.
At a strategic level, AI will produce models of battlefields and propose how to respond to attacks, maybe even including the use of nuclear weapons.
"We need to ensure and safeguard a space for proper human control over the choices made by artificial intelligence programmes: human dignity itself depends on it," Francis said.
The Argentine pontiff was speaking after a series of meetings with world leaders, including Ukrainian President Volodymyr Zelensky, France's Emmanuel Macron and Canadian Prime Minister Justin Trudeau.
'Serenity, smiles'
Francis had spent the morning clowning around with comedians at the Vatican, including Whoopi Goldberg, Chris Rock and Jimmy Fallon.
He met more than 100 "artists from the world of humour" as part of his efforts to engage with contemporary culture.
"Instead of reading my speech, I'll just do this", the grinning pontiff said, as he stuck his thumb in his ear and wiggled his fingers at a room full of humorists.
But he had a serious message too for the comedians gathered from 15 countries, from Argentina to Germany and East Timor.
"Immersed as we are in many social and personal emergencies, you have the power to spread serenity and smiles," the pope told them.
"You are among the few to have the ability to speak to very different people, from different generations, backgrounds and cultures," Francis said.
The 107 comedians included Britain's Stephen Merchant, from TV show "The Office", US stand-up comedian Rock, and Italy's Silvio Orlando, who played a scheming cardinal in "The Young Pope".
Seconds before Francis arrived, Fallon, host of the "Tonight Show" in the United States, had the room in fits of laughter as he pranced around at the front.
"Sister Act" star Goldberg and Julia Louis-Dreyfus of "Seinfeld" fame waved from the front row as the pope entered the gilded and frescoed room at the Vatican.
Goldberg has previously joked about offering the pope a cameo in "Sister Act 3".
Asked if she pressed Francis on it Friday, she quipped that "it wasn't the right moment, I'll probably send him an email", according to ANSA news agency.