The Vatican has a deep history of conflict mediation, with varying degrees of success. An effort by the pope to end the war in Ukraine would face long odds.

The Pope is the only one capable of protecting these people,’ Ukraine’s top Catholic leader tells Leo XIV in personal Vatican appeal.

President Trump suggested Monday after a call with Russia's Vladimir Putin that ceasefire negotiations between Moscow and Kyiv should take place in the Vatican, hosted by Pope Leo XIV. Why it matters: This would be a high-profile and potentially risky first act of international diplomacy for the American-born pope.