The United Nations High Commissioner for Human Rights warned Russia on Tuesday over use of incendiary weapons in air strikes on the Syrian city of Aleppo, where he said attacks on civilian targets may amount to crimes against humanity. The situation in besieged, rebel-held eastern Aleppo demanded bold new initiatives "including proposals to limit the use of the veto by the permanent members of the Security Council", said High Commissioner Zeid Ra'ad al Hussein. That would enable major powers to refer the situation to the International Criminal Court, a step previously blocked by Russia and China. "Such a referral would be more than justified given the rampant and deeply shocking impunity that has characterized the conflict and the magnitude of the crimes that have been committed, some of which may indeed amount to war crimes and crimes against humanity," Zeid said in a statement. When asked how Russia viewed the suggestion of limiting the veto rights of permanent Security Council members, Kremlin spokesman Dmitry Peskov said: "Negatively". Russia's Foreign and Defense Ministries did not immediately respond to requests for comment. Last week Peskov said the Russian air force would continue to support Syrian government troops and that what he called the "war on terror" would continue. Zeid said Syria's government and its allies had undertaken a "pattern of attacks" against targets protected by international law, including medical units, aid workers and water-pumping stations. Zeid, a former Security Council president, was not advocating abolishing the veto, but lifting it for very serious cases of international crimes, his spokesman Rupert Colville said. "Look at Aleppo, look what's happening. I think you will never have a more compelling case for something serious, action to be taken," Colville told a U.N. briefing. Russia's U.N. veto power, together with its military involvement on the side of President Bashar al-Assad, has given it formidable leverage in the Syria crisis, frustrating the United States. BANNED BY TREATY Zeid said that dropping indiscriminate incendiary weapons in heavily populated areas was particularly concerning, as well as being banned by a treaty that Russia is bound by. He compared Aleppo to the World War Two battles of Warsaw and Stalingrad and the attack on Dresden, and said calling the enemy a "terrorist organization" was not an excuse to ignore the laws of war The rebels' use of inaccurate "hell-fire cannons", homemade mortars that fire gas cylinders packed with explosives and shrapnel, was also totally unacceptable, he said. World Health Organization spokeswoman Fadela Chaib said that between Sept. 23 and Oct. 2, 342 people had been killed in eastern Aleppo,including 106 children, and 1,129 had been wounded, including 261 children. Those figures were based on reports from functioning health centers and the true figures were probably much higher, she said. "As of yesterday, we have now only six partially functional hospitals that are in service, only one hospital that offers trauma care services," Chaib told the briefing. WHO still hopes to be able to evacuate dozens of wounded and chronically ill from Aleppo, she said. "We are preparing plans, we are in contact with several hospitals inside and outside the country, but unless there is security and access we cannot move." The Syrian government has yet to respond to a U.N. plan for aid convoys in Syria during the month of October, U.N. spokesman Jens Laerke said, noting that the last "cross line" convoy was on Sept. 25.