ABOARD THE PAPAL PLANE (RNS) – Pope Leo XIV said the war in Iran does not qualify as a just war according to Catholic teaching, while answering questions by journalists aboard the papal plane for his six-day visit to Spain.

“I believe it has been already declared clearly,” Leo said answering a question by Italian journalist Franca Giansoldati, of Il Messaggero, on Saturday (June 6). “There is no just war there,” he said referencing the conflict in Iran.

The question referred to Vice President JD Vance’s remarks in April, where he used just war theory to justify the war in Iran. On that occasion, Vance said the pope should “be careful” when talking about theology.

“When the pope says that God is never on the side of people who wield the sword, there is more than 1,000-year tradition of just war theory,” he said. President Trump later said Leo was “weak” on war in a post on Truth Social.

Leo pointed to his most recent encyclical, Magnifica Humanitas (Magnificent Humanity), which says that just war theory is “too often been used to justify any kind of war” and is “now outdated.”

“The problem is that the just war theory comes from centuries past when we couldn’t imagine the weapons, human being’s ability for destruction,” Leo said.

The document urges alternative ways to overcome conflict, “dialogue, diplomacy and forgiveness,” condemning the use of force which disproportionately harms civilians.

The pope made “overcoming the theory of the ‘just war,'” one of the themes of the first summit of cardinals he convened at the Vatican June 26-27, called a consistory. 

Aboard the plane, Leo also weighed in on the war in Ukraine, especially after Russian President Vladimir Putin recently refused to meet with Ukrainian President Volodymyr Zelenskyy. “I am worried for Ukraine,” Leo said, “We must really push to reach an end to the conflict and the war and find a solution,” he added, calling for continued negotiations.

“Already, four years and a half have passed. We must reach a solution,” he said, recognizing the United States’ efforts to mediate a peace.

The pope also said he is in contact with the religious leaders in Lebanon, whom he met when he visited the country in November. “The situation is very complex,” he said, as Israel continues its offensive in the southern part of the country.

Regarding clerical sexual abuse, which he will likely address during his visit to Spain when he meets with abuse victims, Leo said “abuse remains an open wound.”

Finally, Leo said he will support the United States in the soccer world cup, though he does not know how many games he will be able to watch. He also said that while “the pope is for all teams, Prevost is for Madrid!,” using his former last name.

He addressed the rise in religiosity among some young people in many European countries and parts of the United States. “Young people that are looking for something more, having grown up in many cases that, if you will, spiritual dimension in their lives, they realize there’s an emptiness and a lack of a sense of meaning” he said, adding that he hopes his visit to Spain will encourage the young who have drawn closer to the church there.

Leo also commented on the Puerto Rican singer Bad Bunny, who is doing ten concerts in Madrid this month, amid rumors of a possible virtual meeting between the two. “If (young people) are confronted with the question: do they want to see the Bad Bunny or do they want to see the pope, I think many will see Bad Bunny. But I think there will also be a few here to see the pope. And that says something, you know?”