Pope Leo has urged world leaders to end what he called the “madness of war,” in an impassioned appeal, as senior US and Iranian officials met in Pakistan to discuss ending the six-week conflict, Reuters reports.

At a special prayer vigil in St. Peter’s Basilica, the first American pontiff decried the use of religious language to justify war and said a “delusion of omnipotence that surrounds us … is becoming increasingly unpredictable”.

Making a direct appeal to world leaders, he said: “Stop! It is time for peace! Sit at the table of dialogue and mediation, not at the table where rearmament is planned.”

Leo, who is known for choosing his words carefully, has emerged as an outspoken critic of the Iran war.

On Saturday, he used forceful language to denounce conflict, citing letters from children in war zones he said described “horror and inhumanity”.

“Enough of the idolatry of self and money!” Leo said. “Enough of the display of power! Enough of war!”