President Volodymyr Zelensky said that China has, for the first time, responded forcefully to Russian rhetoric about the possible use of nuclear weapons.

According to Zelensky, European partners and international leaders discussed the issue with him during negotiations around the NATO summit, where China’s role in the war—especially in relation to nuclear messaging—became a central topic.

Zelensky said he was told that the Chinese side reacted “very harshly” to voices in Russian media suggesting nuclear weapons could be used in response to Ukrainian strikes. He described the Chinese response as direct and clear, stressing that China informed Russia—reportedly in ultimatum form—that the use of nuclear weapons is inadmissible and that there cannot even be contemplation of such an option.

On China’s broader role in ending the war, Zelensky said the situation has “changed a bit,” pointing to indications that Beijing has taken a tougher line than before.