Pope Leo said aeroplanes should be “carriers of peace” and that aerial bombardments should be banned in his latest condemnation of war amid the US-Israeli conflict with Iran.

The comments were made by Leo, the Catholic church’s first American pontiff, during a meeting on Monday with staff from the Italian national airline, ITA Airways.

“Airplanes should always be carriers of peace, never of war! No one should be afraid that threats of death and destruction might come from the sky,” the pope said. He did not specifically refer to the war on Iran.

Leo added: “After the tragic experiences of the 20th century, aerial bombings should have been banned for ever. Instead, they still exist, and technological development, positive in itself, is being placed at the service of war. This is not progress; it is regression!”

The pope’s criticism of the war was more pointed on Sunday, when during his weekly Angelus prayer at St Peter’s Square he renewed his appeal for a ceasefire. He described the death and suffering caused by the conflict as a “scandal to the whole human family”.

He said he had been following the situation with “dismay”.

“We cannot remain silent in the face of the suffering of so many people, the defenceless victims of these conflicts. What hurts them hurts the whole of humanity,” the pope added.

“I strongly renew my appeal for us to persevere in prayer, so that hostilities may cease and the way may finally be paved for peace.”

Leo, who was elected pope in May last year after the death of Pope Francis, has so far been cautious over his engagement with the US president, Donald Trump. He has relied instead on his college of cardinals to directly criticise the US’s decision to go to war in Iran.

Earlier this month, Cardinal Domenico Battaglia in Naples addressed an open letter to “the merchants of death” profiting from weapons’ sales, while Washington DC Cardinal Robert McElroy said the conflict “fails to meet the just war threshold for a morally legitimate war”.