Russian President Vladimir Putin suspended Moscow’s participation in the last remaining nuclear arms control pact with the United States, announcing the move Tuesday in a bitter speech in which he made clear he would not change his strategy in the war in Ukraine.

Putin emphasized, however, that Russia isn’t withdrawing from the pact yet, and hours after his address the Foreign Ministry said Moscow would respect the treaty's caps on nuclear weapons. It also said Russia would continue to exchange information about test launches of ballistic missiles per earlier agreements with the United States.

In his long-delayed state-of-the-nation address, Putin cast his country — and Ukraine — as victims of Western double-dealing and said it was Russia, not Ukraine, fighting for its very existence.

“We aren’t fighting the Ukrainian people,” Putin said ahead of the war’s first anniversary Friday. “The Ukrainian people have become hostages of the Kyiv regime and its Western masters, which have effectively occupied the country.”

The speech reiterated a litany of grievances he has frequently offered as justification for the widely condemned military campaign, while vowing no military letup.

Along with limits on the number of nuclear weapons, the 2010 New START envisages broad inspections of nuclear sites. Putin said Russia should stand ready to resume nuclear weapons tests if the U.S. does so, a move that would end a global ban on such tests in place since the Cold War era.

U.N. Secretary-General Antonio Guterres responded by calling for Russia and the United States to return to dialogue immediately because “a world without nuclear arms control is a far more dangerous and unstable one.”

U.S. Secretary of State Antony Blinken described Moscow’s decision to suspend participation in the treaty as “really unfortunate and very irresponsible."

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“We’ll be watching carefully to see what Russia actually does,” he said while visiting Greece.

China’s U.N. Ambassador Zhang Jun called on the U.S. and Russia to “continue to negotiate with each other in finding a good solution.”

U.S. President Joe Biden, speaking in Poland a day after his surprise visit to Ukraine, did not mention the START suspension but blasted Putin for the invasion. He pledged continued support for Ukraine despite “hard and bitter days ahead.”

“Democracies of the world will stand guard over freedom today, tomorrow and forever,” Biden said at Warsaw's landmark Royal Castle before a cheering crowd of Poles and Ukrainian refugees.

Putin's announcement was the second time in recent days the Ukraine war showed it could spread into perilous new terrain, after Blinken told China over the weekend that it would be a “serious problem” if Beijing provided arms and ammunition to Russia.

China and Russia have aligned their foreign policies to oppose Washington. Beijing has refused to condemn Russia’s invasion or atrocities against civilians in Ukraine, while strongly criticizing Western economic sanctions on Moscow. Late last year, Russia and China held joint naval drills.

The deputy head of Ukraine’s intelligence service, Vadym Skibitskyi, told The Associated Press his agency hasn’t seen any signs so far that China is providing weapons to Moscow.

Russia invaded Ukraine on Feb. 24, 2022, and made a dash toward Kyiv, apparently expecting to overrun the capital quickly. But stiff resistance from Ukrainian forces — supported by Western weapons — turned back Moscow's troops. While Ukraine has reclaimed many areas initially seized by Russia, the sides have become bogged down elsewhere.

The war has revived the divide between Russia and the West, reinvigorated the NATO alliance, and created the biggest threat to Putin's rule of more than two decades.

In Tuesday's speech, Putin again offered his own version of recent history, discounting Ukraine's arguments that it needed Western help to thwart a Russian military takeover. He has repeatedly depicted NATO’s expansion to include countries close to Russia as an existential threat to his country.

“It’s they who have started the war. And we are using force to end it,” he said before an audience of lawmakers, officials and soldiers, and broadcast on all state TV channels.

Italian Premier Giorgia Meloni, who was in Ukraine on Tuesday, said she wished Putin had taken a different approach.

“What we heard this morning was propaganda that we already know,” Meloni said in English. “He says (Russia) worked on diplomacy to avoid the conflict, but the truth is that there is somebody who is the invader and somebody who is defending itself.”

Also meeting with Zelenskyy was the newly appointed chairman of the U.S. House Foreign Affairs Committee, who led a delegation for the first time since the start of the war and since Republicans won control of the House of Representatives.

Chairman Mike McCaul and a handful of other GOP lawmakers said they had a productive meeting about what Zelenskyy needs for winning the war. He provided them with a list of weapons, including longer-range artillery and air-to-surface systems.

The meeting comes as some hard-right Republicans are vowing to block future U.S. aid to Ukraine. “We have seen time and again the majority of Republicans and Democrats support our assistance to Ukraine,” McCaul said in a statement. “But the Biden administration needs to lay out their long-term strategy.”

Putin denied any wrongdoing in Ukraine, even after Kremlin forces struck civilian targets, including hospitals, and are widely accused of war crimes.

Zelenskyy cited fresh attacks on Ukrainian civilians Tuesday, and downplayed Putin’s speech.

“I have not watched it, because during this time there were missile strikes on Kherson. Twenty-one people were wounded and six were killed,” he said.

Putin also accused the West of taking aim at Russian culture, religion and values. He fired another broadside at Western gender policies that he described as efforts to destroy “traditional” values.

And he said Western sanctions hadn’t “achieved anything and will not achieve anything.” He blasted Russian tycoons who kept their assets in the West and saw them confiscated or frozen as part of the sanctions.

“Believe me, ordinary people had no sympathy for those who lost their yachts, palaces and other assets abroad,” Putin said.

While Russia’s Constitution mandates that the president deliver the state-of-the-nation speech annually, Putin never gave one in 2022. Last year, the Kremlin also canceled two other big annual events — Putin’s news conference and a highly scripted phone-in marathon taking questions from the public.

Reflecting the Kremlin's clampdown on free speech and press, it barred in-person coverage of the address by media from “unfriendly” countries, including the U.S., the U.K. and those in the European Union.