Zelensky believes that Putin may use nuclear weapons in Ukraine

Ukrainian President Volodymyr Zelensky told CNN on Friday that "all of the countries of the world" should be prepared for Russian President Vladimir Putin to use tactical nuclear weapons in a war against Ukraine.

Zelensky told CNN's Jake Tapper in an exclusive interview from the President's Office in Kyiv on Friday that Putin could turn to either nuclear or chemical weapons because he does not value the lives of the people of Ukraine.

"Not only me – all of the world, all of the countries have to be worried because it can be not real real information, but it may be truth," Zelensky said, speaking in English.

"Chemical weapons, they should do it, they could do it, for them the life of the people, nothing. That is why," Zelensky said. "We should think not be afraid, not be afraid but be ready. But that is not a question for Ukraine, not only for Ukraine but for all the world, I think."