Quiet night in Ukrainian capital as Russia orders nuclear forces on high alert

President Vladimir Putin has dramatically escalated East-West tensions by ordering Russian nuclear forces to be put on high alert as the invasion of Ukraine continues.

Explosions and gunfire that have disrupted life in the Ukrainian capital Kyiv since the start of the invasion appeared to subside overnight as the Kremlin’s military advances were slowed by an outgunned but determined resistance.

Ukraine’s embattled leader Volodymyr Zelensky has agreed to talks with Moscow, and Western nations plan to send arms and other supplies to the country’s defenders.

In a bid to shore up the plummeting rouble, Russia’s central bank has sharply raised its key rate from 9.5% to 20% amid crippling Western sanctions.

Citing “aggressive statements” by Nato and tough financial sanctions, Mr Putin issued a directive to increase the readiness of Russia’s nuclear weapons, raising fears that the invasion of Ukraine could lead to nuclear war, whether by design or mistake.

A senior US defence official said the Russian leader is “potentially putting in play forces that, if there’s a miscalculation, could make things much, much more dangerous”.

Mr Putin’s directive came as Russian forces encountered strong opposition from Ukraine defenders.

Moscow has so far failed to win full control of Ukraine’s airspace, despite advances across the country. US officials say they believe the invasion has been more difficult, and slower, than the Kremlin envisioned, though that could change as Moscow adapts.

The conflict – seemingly more quiet overnight on Sunday than in previous nights – could evolve significantly if Russia gets military help from neighbouring Belarus, which is expected to send troops into Ukraine as soon as Monday, according to a senior American intelligence official.

The official said that whether Belarus enters the war depends on Ukraine-Russia talks set to take place in the coming days.

Amid the mounting pressure, Western nations said they would tighten sanctions and buy and deliver weapons for Ukraine, including Stinger missiles for shooting down helicopters and other aircraft.

European countries will also supply fighter jets to Ukraine, EU foreign policy chief Josep Borrell said.

Mr Zelensky’s office, meanwhile, announced plans for a meeting with a Russian delegation at an unspecified location on the Belarusian border.

It was not immediately clear when the meeting would take place, nor what the Kremlin was ultimately seeking, either in those potential talks on the border or, more broadly, from its war in Ukraine.

Western officials believe Mr Putin wants to overthrow Ukraine’s government and replace it with a regime of his own, reviving Moscow’s Cold War-era influence.

The fast-moving developments came as scattered fighting was reported in Kyiv. Battles also broke out in Ukraine’s second-largest city, Kharkiv, and strategic ports in the country’s south came under assault from Russian forces.

By late on Sunday, Russian forces had taken Berdyansk, a Ukrainian city of 100,000 on the Azov Sea coast, according to Oleksiy Arestovich, an adviser to Mr Zelensky’s office.

Russian troops also made advances toward Kherson, another city in the south of Ukraine, while Mariupol, a port city on the Sea of Azov that is considered a prime Russian target, is “hanging on”, Mr Arestovich said.

With Russian troops closing in around Kyiv, a city of almost three million, the mayor of the capital expressed doubt that civilians could be evacuated.

Authorities have been handing out weapons to anyone willing to defend the city. Ukraine is also releasing prisoners with military experience who want to fight, and training people to make firebombs.

Meanwhile, the top official in the EU outlined plans by the 27-nation bloc to close its airspace to Russian airlines and buy weapons for Ukraine.

European Commission president Ursula von der Leyen said the EU will also ban some pro-Kremlin media outlets.

The US also stepped up the flow of weapons to Ukraine, announcing it will send Stinger missiles as part of a package approved by the White House on Friday. Germany likewise plans to send 500 Stingers and other military supplies.

The 193-member UN General Assembly has scheduled an emergency session on Monday over Russia’s invasion.

Mr Putin, in ordering the nuclear alert, cited not only statements by Nato members but the hard-hitting financial sanctions imposed by the West against Russia, including the Russian leader himself.

In televised comments, Mr Putin said: “Western countries aren’t only taking unfriendly actions against our country in the economic sphere, but top officials from leading Nato members made aggressive statements regarding our country.”

US defence officials would not disclose their current nuclear alert level except to say that the military is prepared all times to defend its homeland and allies.

White House press secretary Jen Psaki told ABC that Mr Putin is resorting to the pattern he used in the weeks before the invasion, “which is to manufacture threats that don’t exist in order to justify further aggression”.

The practical meaning of Mr Putin’s order was not immediately clear. Russia and the United States typically have land and submarine-based nuclear forces that are on alert and prepared for combat at all times, but nuclear-capable bombers and other aircraft are not.

In Kyiv, terrified residents hunkered down in homes, underground garages and subway stations in anticipation of a full-scale Russian assault. Food and medicine were running low, Mayor and former boxing champion Vitali Klitschko said.

“Right now, the most important question is to defend our country,” Mr Klitschko said.

Russia’s failure thus far to win full control of Ukraine’s airspace is a surprising lapse that has given outgunned Ukrainian forces a chance to slow the advance of Russian ground forces.

Normally, gaining what the military calls air superiority is one of the first priorities for an invading force.

But even though Russian troops are being slowed by Ukrainian resistance, fuel shortages and other logistical problems, a senior US defence official said that will probably change.

“We are in day four. The Russians will learn and adapt,” the official said.

The number of casualties from Europe’s largest land conflict since the Second World War remains unclear amid the confusion.

Ukraine’s interior ministry said on Sunday that 352 Ukrainian civilians have been killed, including 14 children. It said an additional 1,684 people, including 116 children, have been wounded.

The Russian defence ministry gave no figures on Russia’s dead and wounded but said on Sunday the country’s losses were “many times” lower than Ukraine’s.

The US, European Union and UK have also agreed to block selected Russian banks from the Swift system, which moves money around thousands of banks and other financial institutions worldwide.

Russia’s economy has taken a pounding since the invasion, with the rouble plunging, prompting the central bank’s move to hike its key rate from 9.5% to 20%.