Putin, as part of the 2022 invasion of Ukraine, said that if any countries tried to stop Russia, they would face "such consequences that you have never encountered in your history". It's hard to take that two ways.

Also, much of the point isn't who has threatened to use them. The more nuclear weapons material floating around, the more chance that it lands in the hands of someone with no compunctions about actually using it. The Doomsday Clock gets closer to midnight every time another country gets nukes.