The top United Nations human rights official said on Friday that the siege and bombing of eastern Aleppo in Syria constituted 'crimes of historic proportions' that have caused heavy civilian casualties amounting to war crimes. Zeid Ra'ad al Hussein, in a speech by video to the UN Human Rights Council in Geneva, called again for major powers to put aside their differences and refer the situation in Syria to the prosecutor of the International Criminal Court (ICC). Paulo Pinheiro, chairman of the UN commission of inquiry on Syria who addressed the special session, said that the panel would continue to document war crimes in Aleppo and appealed to the government of President Bashar al-Assad to provide information on violations.