The first international reactions to Pope Leo XIV’s inaugural encyclical have begun to emerge less than 24 hours after its publication, with bishops, politicians and technology figures across the United States, Britain and Canada welcoming the document’s warnings about the dangers posed by artificial intelligence.

The encyclical, Magnifica Humanitas, was released by the Vatican on 25 May and is already being compared to Pope Leo XIII’s landmark 1891 social encyclical Rerum Novarum, which addressed the upheavals of the Industrial Revolution. Pope Leo XIV deliberately dated the text 15 May to coincide with the 135th anniversary of the earlier document.

One of the strongest official political reactions came from the United States ambassador to the Holy See, Brian Burch, who praised the Vatican’s intervention in the growing global debate surrounding AI.

“We welcome the Holy See’s important contribution to the subject of artificial intelligence,” Burch said. “The Vatican’s moral leadership on technology and human dignity contributes meaningfully to the global conversation on AI.”

Burch said the United States shared the Holy See’s commitment to ensuring that artificial intelligence “serves humanity and upholds fundamental values”, while also defending the Trump administration’s emphasis on innovation and American leadership in the sector.

“The United States is likewise committed to exporting American AI technologies built on principles of transparency, security and human flourishing, ensuring the world benefits from AI systems that reflect democratic values rather than authoritarian control,” he said.

David Sacks, the technology investor and former White House AI adviser, also responded publicly to the encyclical, agreeing with the Pope’s argument that AI should remain a tool at the service of humanity rather than become an instrument of “domination or exclusion”.

Writing on X, however, Sacks questioned how governments could be trusted with increased regulatory authority over artificial intelligence. “If we hand governments sweeping power over AI development in the name of safety, how do we prevent it from being used to censor, surveil and control citizens, as Orwell foretold in 1984?” he wrote.

“This is the real alignment problem. The oldest questions of human nature and authority don’t disappear in the AI age. They become newly relevant.”

The encyclical also drew praise from Democratic Senator Chris Murphy of Connecticut, who said Pope Leo XIV had articulated growing concerns about the social and moral effects of artificial intelligence.

“AI threatens to undermine the basic building blocks of humanity as it seeks to replace our most basic functions, like creativity, friendship and critical thinking,” Murphy wrote, describing the Pope’s warning against monopolisation of AI technologies by powerful corporations as “really important”.

Catholic bishops throughout the English-speaking world moved quickly to welcome the document, presenting it as a major contribution to Catholic social teaching at a moment of rapid technological change.

Archbishop Paul S. Coakley of Oklahoma City, president of the United States Conference of Catholic Bishops, said the Church in the United States received the encyclical “with gratitude and praise”.

“It is a powerful reminder that no technology can replace a child of God, and all technology should be placed at the service of helping humanity thrive,” he said. Drawing parallels with Rerum Novarum, Archbishop Coakley said Pope Leo XIV had shone “the light of the Gospel and the tradition of the Church” on the opportunities and dangers created by artificial intelligence.

“The Pope calls us to never lose sight of the inherent dignity of all human life and the moral imperative for technology to support peace and the common good rather than the limited interests of a few,” he said.

The Archbishop also revealed that the US bishops’ conference had already tasked its doctrine committee with coordinating the Church’s response to developments in artificial intelligence.

In England and Wales, Archbishop Richard Moth, president of the bishops’ conference, and the Archbishop of Westminster described the encyclical as “an important contribution to integral human development during a time of considerable change”.

“One of the first interventions of Pope Leo since he was elected Pope was to draw attention to the profound challenges AI will bring to humanity,” Archbishop Moth said.

The Archbishop of Westminster noted that the Church’s social teaching tradition since Rerum Novarum offered substantial guidance for navigating technological and economic upheaval. “We must respond to these, placing the centrality of humanity above all else, most especially the solidarity that is needed if we are to seek peace among peoples,” he said. “Pope Leo reminds us that ‘more powerful does not necessarily mean better.’”

Archbishop Moth warned that technology “must not be used to embed unjust economic systems and abuses of power, but must always be at the service of human development”.

He also disclosed that the Bishops’ Conference of England and Wales had established a working group to study the encyclical and examine the ethical issues generated by artificial intelligence.

Other American bishops issued similar statements within hours of publication. Bishop Michael Burbidge of Arlington said the encyclical was especially welcome “in this time of tremendous social and technological change”.

“I encourage all to join me over the coming days in reading Magnifica Humanitas in its entirety and prayerfully considering all that the Holy Father shares,” Bishop Burbidge said.

Archbishop Richard Henning of Boston described the document as “timely and important”, while Archbishop Nelson Pérez of Philadelphia encouraged Catholics to reflect on its “vital message” concerning the protection of human dignity during rapid technological development.

Bishop William Koenig of Wilmington, Delaware, said the encyclical drew upon the wisdom of Catholic social teaching to ensure that technological progress remained directed towards “human flourishing”.

The Canadian Conference of Catholic Bishops also welcomed the document, saying it offered guidance for protecting the human person during “a profound epochal shift”.

The bishops highlighted the encyclical’s call for “a civilization of love founded on justice, dialogue and shared responsibility” as an alternative to what the Vatican described as “the culture of power and war”.

However, a more critical reaction came from the Bishop Emeritus of Tyler, Bishop Joseph Strickland, who published a lengthy critique arguing that Magnifica Humanitas risked placing excessive emphasis on social structures and human flourishing at the expense of sin, repentance and salvation. While acknowledging the encyclical’s “strong and important” rejection of transhumanism and its warnings about “AI warfare, exploitation, digital manipulation and technological domination”, Bishop Strickland said the document devoted comparatively little attention to “original sin, concupiscence, personal repentance, moral culpability, judgment, hell, penance, or the eternal destiny of the soul”.

Bishop Strickland argued that “the roots of evil begin to appear primarily structural rather than spiritual” and warned that the encyclical’s repeated calls for a “civilization of love” risked sounding “less like the fruit of conversion to Christ and more like a global humanitarian project centred on fraternity, solidarity, inclusion and peace”. The former Bishop of Tyler said many Catholics would find the document “deeply unsettling” because “the entire framework is subtly shifting: from God-centredness to man-centredness, from salvation to human flourishing, from sin to systems”.

He concluded by warning against “religious humanism” and insisting that “the answer remains what it has always been: Jesus Christ, King of kings and Lord of lords.”