ABOARD THE PAPAL PLANE (AP) — Pope Francis said Sunday the Vatican was willing to help facilitate the return of Ukrainian children taken to Russia during the war, saying the Holy See had already helped mediate some prisoner exchanges and would do “all that is humanly possible” to reunite families.

“All human gestures help. Gestures of cruelty don’t help,” Francis said during an airborne press conference en route home from Hungary.

Francis also revealed a secret peace “mission” was under way. However, he gave no details when asked whether he spoke about peace initiatives during his talks in Budapest this weekend with Hungarian Prime Minister Viktor Orban or the representative of the Russian Orthodox Church in Hungary.

“I’m available to do anything,” Francis said. “There’s a mission that’s not public that’s underway; when it’s public I’ll talk about it.”

The International Criminal Court last month issued an arrest warrant for Russian President Vladimir Putin and Russia’s children’s commissioner, accusing them of war crimes for abducting children from Ukraine.

Russia has denied any wrongdoing, contending the children were moved for their safety.

Last week Ukrainian Prime Minister Denys Shmyhal met with Francis at the Vatican and asked him to help return Ukrainian children taken following the Russian invasion.

“I asked His Holiness to help us return home Ukrainians, Ukrainian children who are detained, arrested, and criminally deported to Russia,″ Shmyhal told the Foreign Press Association after the audience.

Francis recalled that the Holy See had facilitated some prisoner exchanges, working through embassies, and was open to Ukraine’s request to reunite Ukrainian children with their families.

The prisoner exchanges “went well. I think it could go well also for this. It’s important,” he said of the family reunifications. “The Holy See is available to do it because it’s the right thing,” he added. “We have to do all that is humanly possible.” ___

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