Pope Francis condemned on Wednesday the latest wave of missile attacks on Ukraine, calling for a ceasefire to avert the risk of escalation of the conflict and asking God to "hurry up" to end it.

He spoke at his general audience in St Peter's Square as NATO allies investigated unconfirmed reports that an explosion in a Polish village near the border with Ukraine was caused by stray Russian missiles. He did not mention the incident.

"I learned with pain and concern of a fresh and even fiercer missile attack on Ukraine, which caused deaths and damage to much civilian infrastructure," Francis said in Italian.

"Let us pray so that the Lord converts the hearts of those who still bet on war and make the desire for peace prevail in martyred Ukraine in order to avoid escalation and to open the path to a ceasefire and dialogue," he said.

A few minutes later, in other comments on Ukraine, he added, "We can pray for Ukraine saying, if you will, 'Hurry up, Lord.'" 

Russia launched 110 missiles and 10 Iranian-made attack drones at Ukraine on Tuesday, the general staff of Ukraine's armed forces said.

Ukrainian President Volodymyr Zelenskiy said the main target of the missile flurry was energy infrastructure, as before, though he added that only 10 intended targets in all had been hit.

The attacks had left millions of Ukrainians without energy in 16 of its 24 regions including Kyiv, the U.N. humanitarian office (OCHA) said.

Last month, Francis, for the first time, directly begged Russian President Vladimir Putin to stop the "spiral of violence and death" in Ukraine.

He has been mentioning Ukraine in nearly all his public appearances and has several times said the crisis was risking the use of nuclear weapons, with uncontrollable global consequences.