The Chinese Foreign Ministry said it's closely following the "nuclear risks triggered" in Ukraine, reiterating that nuclear weapons should not be used in the war with Russia.

A Foreign Ministry spokesperson made the remarks Thursday in response to speculation that the United States is mulling supplying Ukraine with nuclear weapons in a deterrence posture against Russia.

"China is paying close attention to the nuclear risks triggered by the Ukraine crisis and has reiterated time and again that nuclear weapons should not be used and nuclear war must not be fought," Chinese Foreign Ministry spokesperson Mao Ning said, Newsweek reported.

The New York Times reported last week that President Joe Biden could opt to return nuclear weapons that were given up by Ukraine after the fall of the Soviet Union in 1991. Ukraine relinquished the world's third-largest nuclear arsenal in 1994 in exchange for security assurances from the United States, Russia, and Britain. Ukraine accused Russia of violating that agreement with its 2014 annexation of Crimea and 2022 invasion of Ukraine.

Russian President Vladimir Putin on Thursday threatened Ukraine with its new hypersonic missile, Oreshnik, over Ukraine's "continued attacks on our territory by (U.S.) ATACMS missiles."

"Under the current circumstances, all parties need to remain calm and exercise restraint," Mao said. "Joint efforts are needed to cool down the situation through dialogue and consultation to reduce strategic risks."

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