Ukrainian President Volodymyr Zelenskiy says his forces have inflicted "extraordinarily significant" losses on Russia's military in brutal fighting in and around Bakhmut and Vuhledar in the country's Donetsk region.
"The situation is very difficult," Zelenskiy said in a video address on February 19.
"We are breaking the occupier and are inflicting extremely significant losses on Russia. I repeat again and again: The more Russia loses there, the faster we will be able to end this war with the victory of Ukraine."
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Russian forces have suffered massive losses in recent weeks around Bakhmut and Vuhledar, a town that is close to the dividing line between the eastern and the southern theaters of the war.
Ukrainian military drone footage posted last week appeared to show that Russia lost nearly 30 armored vehicles, including tanks and infantry fighting vehicles, in fighting around Vuhledar, which had a population of about 14,000 before the war.
Ukraine reportedly has also suffered heavy losses, but neither side has provided casualty figures for its forces, and battlefield claim are difficult to independently verify.
Earlier, Zelenskiy has pledged that "every Russian attack on…every corner of our state will have concrete legal consequences for the terrorist state," even as the Ukrainian military said Russia continues to conduct offensive operations in several areas of the Kharkiv, Donetsk, and Luhansk regions.
During his previous nightly video address on February 18, Zelenskiy said Kyiv had "received strong signals from our partners and concrete agreements on the inevitability of holding Russia accountable for aggression and terror against Ukraine and its people."
He added that such commitments apply "not only to the evil that Russia has brought since February 24, but also since 2014," referring to Moscow's occupation of Ukraine's Crimea region and its fomenting of a separatist war in parts of eastern Ukraine.
On February 19, the Ukrainian military said there had been continued fighting around several settlements in the Kharkiv, Luhansk, and Donetsk regions. In addition, Russia carried out air strikes against civil infrastructure in the Khmelnytskiy, Dnipropetrovsk, Donetsk, and Kherson regions, including more than 50 attacks from multiple-rocket launchers.
Russia-installed officials told TASS that Ukrainian forces had launched a rocket attack on separatist-controlled Donetsk city, but the report could not be verified.
Ukrainian authorities in the southern region of Kherson said Russian shelling struck the yard of a house in a nearby village, killing three adult members of one family and that four others, including two children, were injured.
"Russian occupiers killed a family in the Kherson region," officials said in a statement. "Three people died at the scene of the tragedy: the father, the mother, and an uncle."
Russian troops were forced to flee Kherson city in November in a major battlefield loss in the south for Moscow.
Meanwhile, Reuters reported that Ukrainian troops near the eastern town of Siversk said they were preparing to defend the area, one of the potential targets of an anticipated Russian offensive.
Siversk is on the road to the larger strategic city of Slovyansk and about 20 kilometers from badly ruined Bakhmut, the scene of deadly fighting and shelling over recent weeks.
The Ukrainian military, in its February 19 statement, said the risk of Russian missile strikes across Ukraine remained high.
WATCH: RFE/RL's Roman Pahulych accompanied a Ukrainian drone crew as they sent up the army's Leleka-100 unmanned aerial vehicle into occupied territory.
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Ukrainian Team Sends Drones Deep Into Russian-Controlled Territory By Night
Over the weekend at the Munich Security Conference -- where discussions about Ukraine dominated events -- U.S. Vice President Kamala Harris said that "the U.S. has formally determined that Russia committed crimes against humanity" in Ukraine.
"Justice must be served," she added, listing allegations of "murder, torture, rape, and deportation."
Russia's ambassador to the United States, Anatoly Antonov, posted a statement rejected the U.S. determination as "an unprecedented attempt to demonize Russia."
European Union foreign policy chief Josep Borrell said on February 19 that he supports an Estonian proposal that the EU purchase ammunition for Ukraine on behalf of member states. Speaking at the Munich Security Conference after the proposal was explained by Estonian Prime Minister Kaja Kallas, Borrell said the EU was "working on" the initiative and that "it will work."
SEE ALSO: The Week's Best: 10 Stories And Videos You Shouldn't MissMeanwhile, U.S. Secretary of State Antony Blinken warned China of "serious consequences" if Beijing supplies weapons to Russia for its war against Ukraine.
In a February 19 interview with U.S. television, Blinken said he told Chinese Foreign Minister Wang Yi the previous day that providing lethal aid to Russia "would have serious consequences in our relationship."
A State Department official said Blinken was "quite blunt" in his warning to Wang, also pressing China not to help Moscow avoid Western sanctions.
February 24 will mark one year since Russia's unprovoked mass invasion of Ukraine, sparking the largest war in Europe since World War II and leading to the deaths of tens of thousands of people and the displacement of millions more.