Pope Leo XIV has rejected Donald Trump’s claim that he supports Iran having a nuclear weapon, insisting instead that the Church has long opposed nuclear arms and that violence must remain a last resort.

Speaking to reporters outside the papal villa at Castel Gandolfo on May 5, the Pope said the Church’s mission is to preach the Gospel and to preach peace. If he is to be criticised for that, he added, then he should at least be criticised truthfully.

Leo’s remarks came after Trump had accused him of being relaxed about the prospect of Iran acquiring a nuclear weapon. The Pope flatly rejected that suggestion, saying there was no ambiguity in the Church’s position and that it had spoken against all nuclear weapons for many years.

At the same exchange with journalists, Leo was asked whether his recent criticism of war applied only to unjust aggressors or also to those acting in self-defence. He replied that self-defence has always been allowed in Catholic teaching, but added that the whole question of just war has become far more complex in the nuclear age and now requires serious re-evaluation.

The Pope went on to argue that dialogue is always preferable to the pursuit of arms, criticising the vast profits made by the arms industry while humanitarian needs, hunger and social distress go unmet. His comments place him squarely within the Church’s longstanding moral unease about war, even while leaving intact the traditional principle that armed force may in limited circumstances be justified.

That position has deep roots in Catholic teaching. The Church has historically allowed self-defence and developed just-war criteria to govern the moral use of force, but Leo’s emphasis suggests a renewed stress on the dangers of modern warfare and the inadequacy of older political reflexes in an age shaped by nuclear threat.

The exchange also comes shortly before Leo’s scheduled meeting with US Secretary of State Marco Rubio, against a backdrop of unusually sharp rhetoric between the Holy See and the Trump camp. Yet the Pope’s intervention was not framed as a political counterattack so much as a restatement of principle: that peace is not weakness, that the Church cannot endorse nuclear arms, and that war must never be treated as a normal instrument of policy.

Leo’s comments were of a piece with the tone he has set since the beginning of his pontificate. From his Easter appeal for those with weapons to lay them down and choose dialogue, to his latest remarks at Castel Gandolfo, he has returned repeatedly to the same theme: that Christian witness in a violent age requires not belligerence but truth, restraint and a determined preference for peace.