Russia’s Vladimir Putin puts nuclear forces on highest-level alert amid strong resistance to invasion of Ukraine

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Russian President Vladimir Putin put his country’s nuclear forces on their highest level of alert, as Ukraine continued to mount a ferocious resistance to the four-day-old Russian invasion of the country.

Shortly after Mr. Putin’s announcement, Ukrainian President Volodymyr Zelensky said he had agreed to talks “without preconditions” aimed at ending the Russian assault, though he wasn’t optimistic they would succeed.

“Honestly, as always, I do not really believe in the outcome of this meeting. But let’s try, so that no citizen of Ukraine would have any doubt that I, as President, did not try to stop the war, when there was a small chance,” Mr. Zelensky said in a video message posted to his official Telegram channel.

More than 400,000 Ukrainians have fled the country since Thursday, when Russia launched a three-pronged attack from the north, east and south. The European Union said on Sunday that it was expecting as many as four million refugees from Ukraine.

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At least 352 Ukrainian civilians have been killed, according to the Ministry of Health. There are no reliable estimates of military losses on either side.

Mr. Zelensky said he had received a promise from Belarusian President Alexander Lukashenko that attacks from Belarusian soil would cease while the Ukrainian delegation was travelling to and from the designated meeting place at the Ukraine-Belarus border. Belarus, a close ally of Moscow, has allowed Russian troops to launch attacks from its territory, enabling the first rapid thrust toward the capital city of Kyiv. That attack appears to have slowed as Russian forces have taken heavy casualties.

Mr. Putin said his country’s heightened nuclear posture was a response to widespread Western sanctions against Russia since the invasion began. On Sunday, Canada joined most of Europe in denying its airspace to Russian carriers. Some Russian banks have been removed from the SWIFT international banking system, and the European Union said it would bar the Kremlin-run RT television network and Sputnik newswire to prevent them from spreading “lies” about Russia’s invasion of Ukraine.

The North Atlantic Treaty Organization military alliance has also deployed additional forward units to member states bordering Russia and Ukraine following the Kremlin’s aggression.

“As you can see, not only do Western countries take unfriendly measures against our country in the economic dimension – I mean the illegal sanctions that everyone knows about very well – but also the top officials of leading NATO countries allow themselves to make aggressive statements with regards to our country,” Mr. Putin said on state television.

“I therefore order the Ministry Defence and Chief of General Staff to put the deterrence forces of the Russian Federation on special combat status.”

Belarus, a close Russian ally, on Sunday held a stage-managed referendum that would allow Mr. Lukashenko, who has run the country since 1994, to extend his rule for another 13 years – while also allowing him to end his country’s status as a non-nuclear state.

“If you [the West] transfer nuclear weapons to Poland or Lithuania, to our borders, then I will turn to Putin to return the nuclear weapons that I gave away without any conditions,” Mr. Lukashenko said, referring to missiles that were stationed on Belarusian territory while it was part of the Soviet Union.

Meanwhile, the battle for Kyiv raged on Sunday, with the city’s mayor saying Ukrainian forces were still in control of this normally graceful city of three million people that Mr. Putin has turned into a war zone.

While Kremlin-controlled media have claimed that Ukrainian troops have been surrendering en masse, Russian forces appeared to be taking heavy losses. In one video posted to social media, a column of at least 10 Russian armoured personnel carriers and infantry fighting vehicles was destroyed in the town of Bucha, on the outskirts of Kyiv, by what appeared to be missile strikes. “Good job, well done,” said a freely swearing local who made the camera-phone footage of the wrecked column.

Kyiv Mayor Vitaly Klitschko said nine children were among those killed in the battle for the capital. But the city’s defences were holding, he said. “Our military, law enforcement and territorial defence continue to detect and neutralize saboteurs,” the former world boxing champ wrote on his Telegram channel.

He said Kyiv residents should remain indoors until Monday, only leaving their homes to go into shelters when air raid sirens sounded. The curfew made independent confirmation of what was happening in the city almost impossible.

The weekend’s loudest explosion came overnight Saturday when a Russian missile slammed into an oil terminal southwest of Kyiv. The blast shook windows and ignited a gigantic blaze at the facility that turned part of the night sky orange. Acrid black smoke poured into the sky over the facility near the town of Vasylkiv throughout Sunday.

Another Russian missile struck an apartment block near Kyiv’s Zhuliany airport, damaging five floors. It wasn’t clear if anyone was hurt, or if residents were already in a bomb shelter.

Russian forces also encountered fierce resistance after pushing into Ukraine’s second-largest city, Kharkiv, on Sunday. One video showed four Russian armoured jeeps captured by Ukrainian soldiers after a battle in the Eastern Ukrainian city involving automatic weapons and rocket-propelled grenades. It wasn’t clear what happened to the Russian soldiers in the jeeps.

Kharkiv resident Natalya Slyusar said she and her family were sheltering in their homes all weekend, with only intermittent electricity and internet. The entrepreneur said her son Yaroslav, who turns 16 on Monday, would spend his birthday sheltering in the bathroom, with no party or presents.

“This district used to be quite a good area for living in, for raising children,” she said of her home on the eastern edge of Kharkiv, close to the Russian border. “But our neighbour – it’s a minus.”

But morale was still high, she said. “We Ukrainians are Cossacks. This is in our DNA. We just forgot this after all the events of the past 200 years. Thanks to Putin, we’ve been reminded.”

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