VATICAN CITY - Pope Leo urged governments to slow the development of AI systems in his first major document, warning they spread misinformation and risk leading the world toward unending war.

The encyclical, titled "Magnifica Humanitas," calls for AI data not to be left solely in private hands, for protections for workers and children, and for cooling competition between AI companies.

"What is needed is a more active political involvement that is capable of slowing things down when everything is accelerating," Leo wrote.

The pope also repudiated the "just war" theory, calling it outdated, and warned that arms industry profits drive conflicts. He apologized for the Church's historical role in slavery.

Leo urged world leaders to address AI risks, invoking the Tower of Babel as a warning against prideful enterprises that "aspire to reach heaven without God's blessing."