Archbishop Desmond Tutu has delivered a scathing report to the UN Human Rights Commission on Israel's shelling of Beit Hanoun in Gaza in 2006.
The report, which was leaked last Monday, says the shelling may have been a war crime.
It criticises an Israeli inquiry that concluded that the shelling was due to a flawed artillery system.
"Nineteen Palestinian civilians were killed in the shelling.
The Israeli military was at the time trying to prevent rocket attacks by Palestinian militants.
"In the absence of a well-founded explanation from the Israeli military - who is in sole possession of the relevant facts - the mission must conclude that there is a possibility that the shelling of Beit Hanoun constituted a war crime," his report said.
The Archbishop also criticised the international community for failing to fulfil its role in respect of the suffering of the people of Gaza.
"It is the silence of the international community in the face of what is happening there which most offends. This silence begets complicity," he said.
Speaking to journalists later he said while the West was feeling penitent "the penance is being paid by the Palestinians."
"I think the West, quite rightly, is feeling contrite, penitent for its awful connivance with the Holocaust," Archbishop Tutu said.
The Israeli delegate at the Human Rights Council, Aharon Leshno-Yaar, rejected the conclusions of the inquiry.
"The mission appears to have legitimised the iron-fisted control of the Hamas terrorist organisation over the Palestinian civilians in the Gaza Strip. It is not clear to me whether such action is appropriate by a representative from the Quartet," he said.
The Palestinian ambassador to the UN, Mohammad Abu-Koash, said: "The Israeli shelling of civilians in Beit Hanoun, while asleep in their homes, and targeting those fleeing, is a war crime, and its perpetrators must be brought before international justice."
Tutu calls for end to Palestinian attacks on Israel
Archbishop Tutu appealed to the UN Human Rights Council to show the same concern for protecting Israelis from Palestinian attacks as it does for Palestinians suffering under Israeli occupation.
The council has been widely criticised for its frequent and heavy criticism of Israel while appearing to soft-pedal on human rights violations elsewhere in the world.
He said Hamas also had an obligation under international law to stop the firing of rockets into Israel.