Ukraine's President Volodymyr Zelenskyy fiercely warned Moscow that it is fostering a deep hatred for Russia among its people by razing cities to the ground, killing civilians, and pushing others into shelters, where they must scavenge for food and water to survive.

"You are doing everything possible to convince our people to abandon the Russian language, because the Russian language will now be associated exclusively with you, with your explosions and murders, with your crimes," Zelenskyy declared in an angry video speech late Saturday.

Russia's invasion of Ukraine has devolved into an attrition battle in many areas, with civilian casualties increasing as Moscow attempts to pound cities into submission from entrenched positions.

Russian missiles targeted the western Ukrainian city of Lviv on Saturday, when President Joe Biden was in neighboring Poland, highlighting Moscow's willingness to strike anyplace in Ukraine, despite its claims to be concentrating its offensive on the country's east.

A toxic odor persisted in the air early Sunday as firefighters in Lviv sprayed water on a charred part of an oil refinery damaged in the Russian attack.

Prokopiv Yaroslav, a security guard at the facility, said he witnessed three rockets impact and demolished two oil tanks, but no one was injured.

"The third strike knocked me down," he explained.

Russia's consecutive bombings rattled the city, which has become a haven for an estimated 200,000 people forced to escape their hometowns. Since the assault began, Lviv has mainly been spared, although rockets struck an airplane repair factory near the city's main airport a week ago.

Olana Ukraine, a 34-year-old information technology expert, said she couldn't believe she had to hide again after escaping the northern city of Kharkiv, one of the war's most heavily bombed places.

"We were on one side of the street when we saw it," she explained. "We observed fire. 'What is this?' I inquired of my acquaintance. Then we heard an explosion and glass shattering. We attempted to conceal ourselves between buildings. I'm not sure what the objective was."

Two cities on opposite ends of the country are currently seeing some of the worst suffering: Chernihiv in the north — strategically placed on the road connecting the Belarusian border with the capital, Kyiv — and Mariupol in the south, an important port city on the Sea of Azov.

Both are surrounded by Russian forces but continue to hold out.

Chernihiv has been under bombardment from the beginning of the invasion. Russia has just demolished the city's central automotive bridge and rendered a nearby pedestrian bridge inaccessible, thus cutting off the last way for citizens to evacuate or food and medication to be delivered in.

Chernihiv's remaining citizens are scared that each explosion, bomb, and body left on the streets will entangle them in the same dreadful net of unavoidable deaths and destruction.

"At night, everyone is talking about Chernihiv becoming the next Mariupol," claimed 38-year-old resident and linguistics scholar Ihar Kazmerchak.

He communicated with The Associated Press via telephone, despite constant warnings indicating that his battery was running low. The city is without electricity, running water, or heat. The list of medications that are no longer available in pharmacies becomes longer by the day.

Kazmerchak begins his day standing in long queues for drinking water, rationed to ten liters (two and a half gallons) per person. When water-delivery trucks make their rounds, residents bring empty bottles and buckets for refilling.

"Food is becoming scarce, and the shelling and bombing continue," he explained.

Mayor Vladyslav Atroshenko reported that more than half of the city's 280,000 residents had already left, and hundreds of those who remained had been slaughtered.

Russian military bombarded residential areas from low altitude in "perfectly clear weather," Atroshenko said Ukrainian media. "They are deliberately destroying civilian infrastructure: schools, kindergartens, churches, residential buildings, and even the local football stadium."

Refugees from Chernihiv who left the encirclement and entered Poland this week talked of widespread and horrific devastation, with bombs demolishing at least two schools in the city center and strikes also destroying the stadium, museums, and a large number of homes.

They claimed that with utilities cut off, residents are drinking water from the Desna and that strikes are killing people as they queue for food. Volodymyr Fedorovych, 77, said he narrowly dodged a bomb that landed on a bread line where he was standing moments before. He stated that the explosion killed 16 individuals and injured many more, including blowing off arms and legs.

The siege is so intense that some of those besieged have lost the ability to fear, Kazmerchak explained.

"Ravaged houses, fires, corpses on the street, and massive aircraft bombs that failed to explode in courtyards no longer surprise anyone," he explained. "People are simply tired of being afraid, and they don't always retreat to basements."

Britain's defense minister said Saturday that the people of Ukraine's besieged cities are unlikely to see a reprieve very soon.

"Russia will continue to employ heavy firepower in urban areas in order to contain its already substantial losses, at the expense of additional civilian casualties," the UK ministry stated.

Previous attacks of hospitals and other nonmilitary targets, including a theater in Mariupol where Ukrainian authorities reported a Russian airstrike killed 300 people last week, have already sparked war crimes claims.

Over ten million people, over a quarter of Ukraine's population, have been displaced by the invasion. According to the United Nations, more than 3.7 million have abandoned the nation, and numerous civilians are suspected of having perished.