Ukrainian President Volodymyr Zelenskyy and Russian Foreign Minister Sergey Lavrov attended the same session of the U.N. Security Council on Wednesday but avoided being in the room at the same time, as the war between their countries is well into its second year with no end in sight.

Zelenskyy, making his first in-person appearance at the U.N. council's chamber in New York since the beginning of Russia's invasion, called for Moscow to lose its veto power as one of the five permanent members of the world body's most powerful panel.

Ukrainian President Volodymyr Zelenskyy (front R) speaks during a U.N. Security Council session in New York on Sept. 20, 2023. (Kyodo) 

He made an appeal for reform of the Security Council to overcome its "deadlock," stressing that the composition of its five permanent members -- also including Britain, China, France and the United States -- does not reflect the realities of the current world.

As he asserted that it has been impossible for the council to help stop the war "because all efforts were vetoed by the aggressor," Russia's delegation was present but without Lavrov.

As part of his proposals, Zelenskyy said that "any participation of the Security Council membership should be suspended for a period of time when such a state resorts to aggression against another nation in violation of the U.N. Charter."

Coinciding with the annual U.N. General Assembly, the meeting of the 15-member council on Russia's war against Ukraine was convened under the theme of "upholding the purposes and principles of the U.N. Charter through effective multilateralism."

Zelenskyy, who left the room before Lavrov appeared, said it is "unjust" that billions of people lack permanent representation on the council and called for it to be expanded to include more countries, such as India and Japan.

The open debate was attended by leaders and top diplomats including Japanese Prime Minister Fumio Kishida and U.S. Secretary of State Antony Blinken.

Kishida, sitting next to Zelenskyy at the iconic horseshoe table, condemned Russia's war against Ukraine and argued it is time to return to the "unshakable principles" of the existing world order and the U.N. Charter, created after World War II.

The Japanese prime minister said the war in Ukraine must end immediately and the international community should step up efforts to "work toward a world of cooperation, not division and confrontation."

"To this end, strengthening the functions of the United Nations is an urgent task," he said. "The Security Council must be enlarged in both its permanent and nonpermanent seats to better reflect the realities of today's world, including Africa."

Lavrov entered the chamber about two hours after the debate began. He delivered a lengthy statement justifying Russia's actions against Ukraine.

Lavrov accused the United States and other Western countries of interfering in internal affairs, while claiming that Russia has fulfilled its obligations under the U.N. Charter.

He said the West "selectively" and "on a case-by-case basis" has used the norms and principles of the charter in an attempt to meet its "selfish geopolitical needs."

Just before Lavrov's remarks, Blinken had his turn and underscored that Russia has "shredded the major tenets" of all kinds of international rules for over a year and half and "flouted one Security Council resolution after another."

"It's hard to imagine a country demonstrating more contempt for the United Nations and all that it stands for -- this from a country with a permanent seat on this council."

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