President Donald Trump said Thursday that he has "to do what's right" as he pushes back against Pope Leo XIV on Iran war.

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"I have to do what's right — the pope has to understand that," Trump told reporters. "I have nothing against the pope. His brother is MAGA all the way."

READ MORE: Fact-checking Trump's claim that Pope Leo supports nuclear weapons in Iran

The U.S. president has maintained that the Iran war is about stopping that country from developing a nuclear weapon and he criticized that country's leadership for killing its own people as he objected to the papal emphasis on peace.

The president added that he's "sure the pope is a great guy," yet he suggested Pope Leo XIV was naive about geopolitics.

"The pope has to understand that this is the real world," Trump said.