Pope Francis has issued yet another appeal for a truce in war-torn Ukraine over the Orthodox Easter weekend celebrated in Russia and the country it invaded for what the pontiff said is "to ease the suffering of exhausted people."

"It is sad that these days, which are the holiest and most solemn for all Christians, we hear the deadly noise of weapons rather than the sound of bells announcing the Resurrection," said Francis in a weekly Vatican Sunday address as Russia's bombardment of cities like Mariupol continued.

Another possible mass grave with as many as 9,000 bodies has been found near the southern city of Mariupol, NPR reported.

Ukraine's blue and yellow flag flew among those who thronged St. Peter's Square to listen to the Pope on April 24.

The Pope recalled the fighting that erupted two months ago after Russia invaded, forcing almost 5.2 million people to flee neighboring countries.

Almost 3 million of them have gone to Poland since the Feb. 24 invasion of Russia into its neighboring country Ukraine which was once part of the Soviet Union.

"May political leaders – please - listen to the voices of your people, who desire peace and not an escalation of conflict," said the Pope.

"Instead of halting, the war has become worse," Francis said, AFP reported.

"It is sad that on these most holy and solemn days for Christians, we hear more of the murderous noise of weapons than that of the bells announcing the resurrection" of Christ.

"I renew the appeal for an Easter truce, the smallest tangible sign of a willingness for peace," he implored.

"Stop the attacks to ease the suffering of exhausted people," the Pope added, with both Russians and Ukrainians celebrating Orthodox Easter on April 24.

Ukraine: ICRC calls for immediate and unimpeded access to Mariupol to facilitate the safe passage of civilians and wounded

In Geneva, the International Committee of the Red Cross said that as a "neutral and impartial intermediary," it is "deeply alarmed" by Mariupol, where the population is in "dire need of assistance."

BESIEGED MARIUPOL

With a peacetime population heading to half a million, that city has been besieged and blockaded for weeks by Russian forces as it is seen as a significant strategic target by Moscow.

"Immediate and unimpeded humanitarian access is urgently required to allow for the voluntary safe passage of thousands of civilians and hundreds of wounded out of the city, including from the Azovstal plant area," said the Red Cross.

The International Red Cross, the ICRC, works with both sides in wars for them to abide by the Geneva Conventions regarding wartime behavior.

Its neutral status can give it access denied to other humanitarian groups and enable it to facilitate prisoner of war exchanges.

Since the end of February, the ICRC said it has worked to reach civilians in need in Mariupol and other cities where civilians are trapped.

"Each day, each hour that passes has a terrible human cost," said the Red Cross.