ROME – The Vatican’s foreign minister is urging the world to resist the “temptation to compromise on Ukraine’s territorial integrity.”

Archbishop Paul Richard Gallagher, secretary of the Section for Relations with States within the Vatican’s Secretariat of State, said on Tuesday that territoriality must be used as a “principle of peace. We hope to start soon a negotiation for a peaceful future.”

The Vatican official was in Ukraine May 18-21, visiting several cities, including Kyiv and Lviv. His comments came during a colloquium on migration at the Pontifical Gregorian University in Rome.

Gallagher is the only high-ranking Vatican authority to speak clearly about Ukraine’s territorial integrity.

“When I was there,” he recounted, “I gathered that there is an appeal toward the Holy See to stay in touch to maintain solidarity. Some countries are very generous but there is a danger of getting tired; we should not think that the problem will solve itself.”

In his more than 50 public appeals for peace following Russia’s invasion of Ukraine, Pope Francis has never spoken about territorial integrity.

In an interview published May 3, the pope said he couldn’t answer “the question of whether it’s right to supply the Ukrainians. The clear thing is that weapons are being tested in that land. The Russians now know that tanks are of little use and are thinking of other things. Wars are made for this: To test the weapons we have produced.”

However, ten days later, Gallagher told Italy’s RAI state television that it is licit for the world to send the country weapons, but that such arms delivery “has to be proportional.”

During his visit to Ukraine, Gallagher said, “The Holy See defends the territorial integrity of Ukraine.”

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Shortly before that, during a press conference in Kyiv on May 20, the archbishop defined the visit as a demonstration of “the closeness of the Holy See and Pope Francis to the Ukrainian people, particularly in light of Russia’s aggression against Ukraine.”

According to the influential Italian blog Il Sismografo, it is “remarkable,” that Gallagher uses direct language, “no turns of phrase, no incisors, to say clearly what he wants to communicate, to make himself understood.”

Follow Inés San Martín on Twitter: @inesanma