Pope Francis has called the bombing of a crowded shopping centre in the city of Kremenchuk the latest in string of "barbarous attacks" against Ukraine.
Ukraine said at least 18 people were killed and about 60 injured on Monday by a Russian missile strike.
Russia's defence ministry said it had hit a legitimate military target in the city, and that the shopping centre was not in use.
"Every day, I carry in my heart dear and martyred Ukraine, which continues to be flagellated by barbarous attacks like the one that hit the shopping centre in Kremenchuk," Francis told crowds in St. Peter's Square on the feast of St. Peter and Paul.
"I pray that this mad war can soon end and I renew my appeal to persevere without tiring in praying for peace.
"May the Lord open the those paths to dialogue which men either do not want or not able to find. May they not neglect to help the Ukrainian population, which is suffering so much," he said.
Australian Associated Press
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