JD Vance has weighed in on Donald Trump’s feud with Pope Leo, effectively telling the pontiff to stay in his lane after the head of the Catholic church criticized the White House over the Iran war.

“It would be best for the Vatican to stick to matters of morality, to stick to matters of what’s going on in the Catholic church and let the president of the United States stick to dictating American public policy,” the vice-president – a Catholic convert himself – said in an interview on Fox News on Monday night.

His comments represented the latest twist in the spat between Trump and the first US-born pope that began on Saturday when Pope Leo XIV suggested during evening prayers at St Peter’s Basilica in Vatican City that a “delusion of omnipotence” surrounded the Iran war.

“Enough of the idolatry of self and money! Enough of the display of power! Enough of war! True strength is shown in serving life,” Leo said in thinly veiled commentary on the direction of the Iran war, and the leaders of the US and Israel who control it.

Trump reacted with anger, posting to his Truth Social platform a lengthy diatribe accusing the pope of being “weak on crime” and “catering to the radical left”, and followed up with a now-deleted AI meme depicting himself as a Jesus Christ-like healer, an act which drew outrage from supporters and opponents alike.

Vance’s entrance into the dispute, and loyal defense of his boss, came after Leo responded on Monday by declaring he did not fear the Trump administration, and would continue to “speak strongly” against war, and for peace.

Asked what he made of the episode, which has angered many in Trump’s evangelical base, Vance tried to brush aside the controversy.

“Sometimes we’re going to have disagreements on matters of public policy,” he said.

“We can respect the pope. We certainly have a good relationship with the Vatican, but we’re also going to disagree on substantive questions from time to time. I think that’s a totally reasonable thing. It isn’t particularly newsworthy.”

Host Bret Baier pressed Vance on Trump’s comment that the pontiff’s position was “hurting” the Catholic church.

“The president has the prerogative to set American foreign policy, he’s got the prerogative to set American immigration policy. He has to look out for the interests of the United States of America, and that inevitably means that when the Vatican comments on issues of public policy, sometimes there’s going to be agreement, of course, and sometimes there’s going to be disagreement,” he said.

“In some cases it would be best for the Vatican to stick to matters of morality, to stick to matters of what’s going on in the Catholic church. But when they’re in conflict, they’re in conflict. I don’t worry about it too much.”

The backlash to Trump’s posting of the AI-generated image, however, clearly resonated at the White House, which took the post down after a furious response from some of the president’s most fervently Christian supporters. One called the image “disgusting and unacceptable”, and another accused Trump of “outrageous blasphemy”.

At a White House event on Monday, Trump took credit for posting the image, and claimed he was portraying himself as a doctor and not a religious healer, despite his caricature wearing religious-style robes and a person at a fictional patient’s hospital bed with their hands clasped together in prayer.

Vance insisted Trump alone made the decision to remove the post, and not because of the criticism it received.

“The president was posting a joke, and of course he took it down because he recognized that a lot of people weren’t understanding his humor,” he said.

“[He] likes to mix it up on social media. One of the good things about this president is that he’s not filtered, he doesn’t send everything through a communications professional. He actually reaches out directly to the people.”

Vance continued critiquing the pope at an event hosted by Turning Point USA on Tuesday, saying he disagreed with Leo’s recent comment that “anyone who is a disciple of Christ … is never on the side of those who once wielded the sword and today drop bombs”.

“I like that the pope is an advocate for peace. I think that’s certainly one of his roles. On the other hand, how can you say that God is never on the side of those who wield the sword?” the vice-president said. “Was God on the side of the Americans who liberated Holocaust camps … It’s very, very important for the pope to be careful when he talks about matters of theology … You’ve got to make sure it’s anchored in the truth.”