Ukrainian President Volodymyr Zelenskyy said Friday that he didn't think a decision had been made to use nuclear weapons, but that it was dangerous to talk about it.

Zelenskyy said that Russia had begun to prepare for a nuclear strike in Ukraine, where Russian forces have been retreating in the wake of a Ukrainian counter-offensive. Zelenskyy said it was very dangerous.

The US dropped atomic bombs in World War II, according to Russian President Vladimir Putin. Western officials are keeping a close eye on Russia for any signs that it may be preparing to use a smaller, tactical nuclear weapon.

US President Joe Biden thinks that Putin is serious about threatening.

Zelenskyy said there was no reason to be fatalistic about a Russian threat that was meant to make Western nations think twice about supporting Ukraine.

They don't know how to use it. They start to talk. They don't know if they'll use it or not, and it's dangerous to speak about it.

Zelenskyy said that Russia was threatening the world with its actions at the Zaporizhia nuclear power plant. "We are one step away from a nuclear accident," the head of the International Atomic Energy Agency warned last month. Fears of another Chernobyl have been raised due to the standoff.

The Ukrainian president wanted his allies to impose more sanctions on Russia.

He said that the world could stop the actions of the Russians. The world can do everything it can to get them to leave the nuclear power plant.