"Evil cannot be trusted," Ukrainian President Volodymyr Zelensky has told the UN General Assembly, as he urged the world to unite to end Russian aggression against his country, reports BBC.
In a passionate speech in New York, Mr Zelensky said a nuclear-armed Moscow must be stopped from "pushing the world to the final war".
He also accused Russia of weaponising everything from food to energy.
Russia's full-scale invasion has prompted widespread condemnation.
In a speech which focused heavily on the danger Russia poses to the world, he argued that other common challenges such as climate change can only be properly addressed after Moscow had been pushed back.
"While Russia is pushing the world to the final war, Ukraine is doing everything to ensure that after the Russian aggression no-one in the world will dare to attack any nation," Mr Zelensky said to world leaders attending the annual General Assembly.
He also said Russia simply had "no right to hold nuclear weapons".
"Weaponisation must be restrained, war crimes must be punished, deported people must come back home, and the occupier must return to their own land.
"We must be united to make it, and we will do it!" Mr Zelensky said.
He also accused Moscow of carrying out "genocide" by abducting Ukrainian children.
In March, the International Criminal Court (ICC) issued an arrest warrant for Russian President Vladimir Putin over the alleged unlawful deportation of Ukrainian children to Russia.
Moscow has repeatedly denied Ukraine's accusations - but a number international experts and organisations point to a growing evidence that Russia has committed war crimes in Ukraine.
The Ukrainian president went on to warn against "shady deals" to try to end the war - the biggest in Europe since World War Two - on unfair terms.
But his key point was to warn the international community that the outcome of the war would affect everyone.
Russia's goal, he said, was to turn Ukraine into "a weapon against you, against the rules based international order".
The peace formula that he had been outlining for months was, he said, not just for Ukraine, but also the rest of the world.
So the pitch was clear and aimed squarely at countries - many of them in the so-called "Global South" including Brazil and India - which have thus far stayed on the side lines.
A number of nations have even strengthened their economic ties with the Kremlin.
Western powers have been rushing around the UN trying to address those countries' wider concerns about development issues and climate change.
Earlier in the day, the Ukrainian leader applauded Joe Biden's speech, in which his US counterpart warned of grave consequences if Russia's aggression was not stopped.
"Russia believes that the world will grow weary and allow it to brutalise Ukraine without consequence. If we allow Ukraine to be carved up, is the independence of any nation secure?" Mr Biden said.
Meanwhile, Iranian President Ebrahim Raisi - whose country has provided combat drones to Russia and is seen as Moscow's key ally - accused Washington of escalating the war in Ukraine.
"The United States of America has fanned the flames of violence in Ukraine in order to weaken the European countries. This is a long-term plan, unfortunately," he told the gathering in New York.