LASK AIR BASE: NATO's chief said Tuesday the alliance sees no need to change its nuclear weapons alert level, despite Russia's threats.
The alliance's secretary-general, Jens Stoltenberg, spoke to The Associated Press following talks on European security with Polish President Andrzej Duda.
They met at an air base in Lask, central Poland, where NATO's Polish and US fighter jets are based.
"We will always do what is needed to protect and defend our allies, but we don't think there is any need now to change the alert levels of NATO's nuclear forces," Stoltenberg said.
The Kremlin has raised the spectre of nuclear war, reporting on Monday that its land, air and sea nuclear forces were on high alert following President Vladimir Putin's weekend order.
NATO itself has no nuclear weapons, but three of its members, the United States, Britain and France, do.
Stoltenberg stressed that Russia has signed a number of agreements, agreeing that nuclear war cannot be won and should not be fought.
The United States recently reinforced the eastern flank of NATO's territory with some 5,000 additional troops.
Valery Gergiev has been fired as chief conductor of the Munich Philharmonic because of his support for Russian President Vladimir Putin and for not rejecting the invasion of Ukraine, the German city's mayor said Tuesday.
Munich Mayor Dieter Reiter announced the decision after Gergiev didn't respond to Reiter's demand that the 68-year-old Russian conductor change course.
"I had expected him to rethink and revise his very positive assessment of the Russian leader," Reiter said.
"After this didn't occur, the only option is the immediate severance of ties."
Gergiev has been Munich's chief conductor since the 2015-16 season.
A day earlier, the Verbier Festival said Gergiev resigned as music director at its request.
Gergiev, a friend and supporter of Putin, is the music director of the Mariinsky Theatre in St.
Petersburg, Russia, and its White Nights Festival.
He was already dropped by the Edinburgh International Festival and from the Vienna Philharmonic's five-concert U.S. tour, and his management company said Sunday it will no longer represent him.
The Rotterdam Philharmonic Orchestra also said it would drop the Russian's planned festival there this September if he doesn't stop supporting Putin.
Milan's Teatro alla Scala said unless Gergiev makes a clear statement in favor of a peaceful resolution in Ukraine, Gergiev wouldn't be permitted to return to complete his engagement conducting Tchaikovsky's "The Queen of Spades," which resumes March 5.
Russian strikes pounded the central square in Ukraine's second-largest city and other civilian targets Tuesday and a 40-mile convoy of tanks and other vehicles threatened the capital.
Ukraine's embattled president accused Moscow of resorting to terror tactics to press Europe's largest ground war in generations.
With the Kremlin increasingly isolated by tough economic sanctions that have tanked the ruble currency, Russian troops advanced on Ukraine's two biggest cities on Day 6 of an invasion that has shaken the 21st century world order.
In Kharkiv, a strategic eastern city with a population of about 1.5 million, explosions tore through the region's Soviet-era administrative building and residential areas.
A maternity ward relocated to an underground shelter.
Ukrainian President Volodymyr Zelenskyy called the targeted attack on Kharkiv's main square "frank, undisguised terror", blaming a Russian missile and calling it a war crime.
"Nobody will forgive. Nobody will forget. This is state terrorism of the Russian Federation."
In an emotional appeal to the European Parliament later, Zelenskyy said: "We are fighting also to be equal members of Europe. I believe that today we are showing everybody that is what we are. We have proven that, as a minimum, we are the same as you."
In addition to the strikes on cities, reports have emerged that Moscow has used cluster bombs on three populated areas.
If confirmed, that would represent a worrying new level of brutality in the war, and could lead to even further isolation in Russia.
Already, with Western powers sending weapons to Ukraine and driving a global squeeze of Russia's economy, President Vladimir Putin's options have diminished as he seeks to redraw the global map, and pull Ukraine's western-leaning democracy back into Moscow's orbit.
The Kremlin denied Tuesday that it has used such munitions and insisted again that its forces only have struck military targets, despite evidence documented by AP reporters of shelling of homes, schools and hospitals.
Unbowed by Western condemnation, Russian officials upped their threats of escalation, days after raising the specter of a nuclear attack.
The Russian defence minister vowed Tuesday to press the offensive until it achieves its goals, while a top Kremlin official warned that the West's "economic war" against Russia could turn into a "real one".
A first round of talks Monday between Ukraine and Russia yielded no stop in the fighting, though both sides agreed to another meeting in coming days.
Throughout the country, many Ukrainian civilians spent another night huddled in shelters, basements or corridors.
More than a half-million people have fled the country, and the UN human rights office said Tuesday that it has recorded the deaths of 136 civilians, including 13 children.
The real toll is likely far higher.
"It is a nightmare, and it seizes you from the inside very strongly. This cannot be explained with words," said Kharkiv resident Ekaterina Babenko, taking shelter in a basement with neighbours for a fifth straight day.
"We have small children, elderly people and frankly speaking it is very frightening."
A Ukrainian military official said Belarusian troops joined the war Tuesday in the Chernihiv region, without providing details.
But just before that, Belarusian President Alexander Lukashenko said his country had no plans to join the fight.
The precision bombing of Kharkiv's Freedom Square, Ukraine's largest plaza, and the nucleus of public life for the city, was a turning point for many Ukrainians, brazen evidence that the Russian invasion wasn't just about hitting military targets but also about breaking their spirits.
The strike blew out or shattered windows and walls of buildings that ring the massive central square, which was piled high with debris and dust.
Inside one building, chunks of plaster were scattered, and doors, ripped from their hinges, lay across hallways.
"People are under the ruins, we have pulled out bodies," said Yevhen Vasylenko, representative of the Emergency Situations Ministry in Kharkiv region.
He said at least six were killed and 20 injured in the strike.
Regional administration chief Oleh Sinehubov said that at least 11 people were killed and scores of others were wounded the day before, during Monday's shelling of the city.
More people were wounded Tuesday, according to authorities.
One after the other, explosions burst through a residential area of Kharkiv in one video verified by AP.
In the background, a man pleaded with a woman to leave, and a woman cried.
Determined for life to go on despite the attacks, hospital workers transferred a Kharkiv maternity ward to a bomb shelter.
Amid makeshift electrical sockets and mattresses piled up against the walls, pregnant women paced the crowded space, accompanied by the cries of dozens of newborns.
Russia's goals in hitting central Kharkiv were not immediately clear.
Western officials speculated that it is trying to pull in Ukrainian forces to defend the city while a larger Russian force encircles Kyiv.
They believe Putin's overall goal is to overthrow the Ukrainian government and install a friendly one.
Zelenskyy said Russia was using the strikes to put pressure on his government.
He did not offer details of the talks between Ukrainian and Russian envoys, but he said Monday night that Kyiv was not prepared to make concessions "when one side is hitting another with rocket artillery".
Meanwhile, Russian troops advanced toward Kyiv, a city of nearly 3 million.
The convoy of armored vehicles, tanks, artillery and support vehicles was 25 km (17 miles) from the centre of the city and stretched about 65 km (40 miles), according to satellite imagery from Maxar Technologies.
In a worrying development, Human Rights Watch has said it documented a cluster bomb attack outside a hospital in Ukraine's east in recent days.
Local residents have also reported the use of the munitions in Kharkiv and the village of Kiyanka near the northern city of Chernihiv, though there was no independent confirmation.
The International Criminal Court chief prosecutor has said he plans to open a Ukraine investigation and is monitoring the conflict.
Flames shot up from a military base northeast of Kyiv, in the suburb of Brovary, in footage taken from a car driving past.
In another video verified by AP, a passenger pleads with the driver, "Misha, we need to drive quickly as they'll strike again".
And Ukrainian authorities released details and photos of an attack Sunday on a military base in Okhtyrka, a city between Kharkiv and Kyiv, saying more than 70 Ukrainian soldiers were killed along with some local residents.
The attack could not be immediately confirmed.
The Russian military's movements have been stalled by fierce resistance on the ground and a surprising inability to dominate Ukraine's airspace.
Ukrainians used resourcefulness to try to stop the Russian advance: On a highway between Odesa and Mykolaiv in southern Ukraine, residents piled tractor tires filled with sand and topped with sandbags to block Russian military convoys.
In Kyiv, sandbags were heaped in front of doors and windows of City Hall.
In the face of that Ukrainian resistance and crippling Western sanctions, Putin has put Russia's nuclear forces on high alert, including intercontinental ballistic missiles and long-range bombers, in a stark warning to the West and a signal of his readiness to escalate the tensions to a terrifying new level.
But a senior US defence official, speaking on condition of anonymity, said the United States had yet to see any appreciable change in Russia's nuclear posture.
Western nations have increased weapons shipments to Ukraine to help its forces defend themselves, but have so far ruled out sending in troops.
As far-reaching Western sanctions on Russian banks and other institutions took hold, the ruble plummeted, and Russia's Central Bank scrambled to shore it up, as did Putin, signing a decree restricting foreign currency.
But that did little to calm Russian fears.
In Moscow, people lined up to withdraw cash as the sanctions threatened to drive up prices and reduce the standard of living for millions of ordinary people.
The economic sanctions, ordered by the US and other allies, were just one contributor to Russia's growing status as a pariah country.
Russian airliners are banned from European airspace, Russian media is restricted in some countries, and some high-tech products can no longer be exported to the country.
International sports bodies moved to exclude Russian athletes, in the latest blow Tuesday, Russians were barred from international ice skating events.