"We call on refraining from the use or the threat of weapons of mass destruction, particularly nuclear weapons and chemical and biological weapons," said a joint statement issued at the United Nations that was also signed by South Africa and Turkey.

Putin this week threatened to use nuclear weapons in the event of a major attack on Russian soil as Ukraine, which his forces invaded in 2022, seeks Western weapons to strike deeper across the border.

Two days after Ukrainian President Volodymyr Zelensky in a UN address accused Russia of planning to attack his country's nuclear reactors, China, Brazil and the other emerging powers said: "Civilian infrastructures, including peaceful nuclear facilities and other energy facilities, should not be the targets of military operation."

China, itself a nuclear power, and Brazil have led calls for mediation to resolve the conflict. Zelensky criticized them by name in his UN address, saying that forcing Ukraine to accept a peace deal was akin to colonialism.

The emerging powers on Friday reiterated "the importance of peaceful solutions for all international conflicts."

"We call for support for a comprehensive and lasting settlement by the parties to the conflict through inclusive diplomacy and political means based on the UN Charter," they said.

Other signatories to the statement were Algeria, Bolivia, Colombia, Egypt, Indonesia, Kazakhstan, Kenya and Zambia.