Putin said on Sunday that leading NATO powers had made “aggressive statements” while imposing hard-hitting financial sanctions against Russia and himself.
At a meeting with his top officials, the president ordered the defence minister and the chief of the military’s general staff to put the nuclear deterrent forces in a “special regime of combat duty”.
The order raises the threat that the tensions could lead to the use of nuclear weapons.
“It’s certainly an escalation,” Al Jazeera’s Moscow correspondent Dorsa Jabbari said. “The last nuclear exercises took place on February 19, when Putin staged very large drills across Russia to test the country’s nuclear programme and [its] readiness.”
The Kremlin said it had successfully test-launched hypersonic and cruise missiles at sea and land-based targets. Belarusian President Alexander Lukashenko, an ally of Putin, also oversaw the military exercises.
“This is seemingly another move by President Vladimir Putin to show that he is still very much a man of strength,” Jabbari said.
The United States responded to Putin’s announcement, accusing the Russian leader of fabricating threats to justify “further aggression”.
“This is a pattern that we’ve seen from President Putin through the course of this conflict, which is manufacturing threats that don’t exist in order to justify further aggression,” White House press secretary Jen Psaki said on ABC.
The American ambassador to the United Nations, Linda Thomas-Greenfield, condemned Putin’s move strongly.
“It means that President Putin is continuing to escalate this war in a manner that is totally unacceptable,” Thomas-Greenfield said in an interview on CBS.
Miro Popkhadze, an analyst at the Foreign Policy Research Institute, told Al Jazeera Putin’s announcement was meant to be perceived as a threat by Europe.
“His objective is to divide the European Union” and weaken the bloc’s support for Ukraine, Popkhadze said. “It is unlikely [this will work].”
Amid the worrying development, the office of Ukraine’s president said a delegation would meet Russian officials near the Belarus border.
Moscow has faced international condemnation since it launched a full-scale invasion of Ukraine on Thursday. Russian troops have faced determined resistance while attempting to enter Ukraine’s big cities, as Ukrainians volunteered en masse to help defend the country, taking guns distributed by authorities and preparing firebombs to fight Russian forces.
Putin has claimed the West failed to take seriously Russia’s security concerns about NATO, the Western military alliance that Ukraine aspires to join.
Secretary-General Jens Stoltenberg on Friday announced that the alliance was deploying thousands of combat-ready troops to Ukraine’s neighbours, as well as continuing to send weapons to Ukraine including air defences after Russia’s attack.
Stoltenberg added that NATO allies and the European Union had already introduced significant sanctions and that other partners around the world had followed suit.
“We must stand ready to do more. Even if it means we have to pay a price,” Stoltenberg said.
Putin sent troops into Ukraine after denying for weeks that he intended to do so, all the while building up a force of almost 200,000 soldiers along the countries’ borders.
He has also expressed scorn about Ukraine’s right to exist as an independent state.
Russia on Thursday took control of the former Chernobyl nuclear plant, where radioactivity is still leaking from history’s worst nuclear disaster 36 years ago.
Radiation levels increased at the Chernobyl Exclusion Zone, Ukraine authorities said on Friday, warning that the seizure of the nuclear plant by invading Russian troops could have “terrible consequences”.