Ukrainian President Volodymyr Zelenskyy in a wartime trip to the United Nations on Tuesday urged the world to stand firm against Russia's "genocide," as he told skeptical developing nations that they had a stake in Kyiv's victory.

Taking the rostrum of the U.N. General Assembly in his trademark military fatigues, Zelenskyy renewed an invitation for world leaders to join a "peace summit" to end the war on Ukraine's terms.

"For the first time in modern history, we have the chance to end the aggression on the terms of the nation which was attacked," Zelenskyy said in a speech met with applause led by Western nations but many empty seats.