The pontiff, who is American, has reportedly made the decision following an “unprecedented” intervention from the Pentagon.

He has also refused an invitation from the US president to attend the nation’s 250th anniversary events on July 4, and will instead visit Lampedusa, a small Mediterranean island that has become an entry point for people attempting to enter Europe from Africa.

Pope Leo XIV (Image: Andrew Medichini)

The pope has repeatedly been outspoken against the US-Israeli war on Iran, branding Donald Trump’s threat to eradicate “a whole civilisation” earlier this week “truly unacceptable”, adding that any attacks on civilian infrastructure would violate international law.

And in his Easter Sunday mass at the weekend, he urged people to reject war and for “those who have weapons [to] lay them down”.

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“Let those who have the power to unleash wars choose peace. Not a peace imposed by force, but through dialogue. Not with the desire to dominate others, but to encounter them,” he said.

Yet the rift between the Vatican and the US government appears to have sparked from a speech in January Pope Leo gave to the Vatican’s diplomatic corps, in which he criticised states seeking conflict around the globe.

The pope is understood to have said that “a diplomacy that promotes dialogue and seeks consensus among all parties is being replaced by a diplomacy based on force, either by individuals or groups of allies”.

Pope Leo XIV at Easter Mass (Image: Andrew Medichini)

The Free Press reports that in the wake of the speech, the US Department of Defence invited Cardinal Christophe Pierre for a meeting, who was serving as Pope Leo’s personal envoy to the US at the time.

The Pentagon requesting a meeting with a Vatican official is understood to be “unprecedented”.

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According to Vatican and US officials who were briefed on the meeting and spoke to The Free Press, the Pentagon criticised the pope’s statements in January, interpreting them as hostile attacks on Trump’s policies.

One Vatican official reported the Pentagon was particularly angered by his apparent questioning of the “Donroe Doctrine”, Trump’s update to the Monroe Doctrine, which calls for the US to be the unchallenged controller of the western hemisphere, the Independent also reports.

The pope is understood to have declined the US’s invitation to July 4 celebrations in the wake of the meeting.

A Vatican official also told The Free Press that the pope has no plans to visit the US while Trump is in office.