BRUSSELS — NATO Secretary General Jens Stoltenberg Wednesday condemned Russian President Vladimir Putin’s announcement on mobilization as “dangerous and reckless nuclear rhetoric.”

“The speech is an escalation, but it is not a surprise. Therefore, we have been prepared. We will stay calm and continue to provide support to Ukraine,” he said in a statement in New York at the margins of the UNGA.

“The speech of President Putin demonstrates that the war is not going according to President Putin’s plans,” the NATO chief noted.

“It’s not new as he has done it many times before. He knows very well that a nuclear war should never be fought and cannot be won, and it will have unprecedented consequences for Russia,” he stressed.

“So the speech, the partial mobilization of the armed forces of Russia just demonstrate that he miscalculated, he made a big strategic mistake and that’s the reason why they now have to do this,” added Stoltenberg.

The NATO chief said the international alliance is staying calm even as Putin has ordered a “partial mobilization” of hundreds of thousands of reservists over the next few months.

Putin’s order comes amid a counteroffensive from Ukraine that has pushed Russian troops back to the border in some places.

“The only way to end this war is to prove that President Putin will not win on the battlefield. When he realizes that, he has to sit down and negotiate a reasonable agreement with Ukraine,” Stoltenberg said.

In a rare address to Russia earlier Wednesday, Putin accused the West of “nuclear blackmail” and made explicit threats about Moscow using its own nuclear arsenal.

“When the territorial integrity of our country is threatened, we, of course, will use all the means at our disposal to protect Russia and our people,” Putin said. “This is not a bluff. And those who try to blackmail us with nuclear weapons should know that the weathervane can turn and point towards them.”

Putin has been garnering more frustration in his own country over his military moves as Ukraine takes back territory.

Russian municipal deputies last week signed a petition calling for Putin to resign, and Chechen leader Ramzan Kadyrov called Russia’s recent retreat in Ukraine “astounding.”

Stoltenberg also said, China’s cooperation with Moscow since Russia’s invasion of Ukraine and Chinese comments against NATO enlargement show why the Western defense alliance should regard Beijing as a security challenge.

“The sum of all is this just increases the importance of NATO allies standing together and realizing that China is part of the security challenges we need to face today and in the future,” Stoltenberg said in an interview with Reuters.

Stoltenberg also noted China’s “coercive behavior” in the South China Sea and against its neighbors as well as “the way they violate basic human rights.” — Agencies