Russian forces in eastern Ukraine captured the center of the railway hub town of Lyman and encircled most of Sievierodonetsk city, Ukrainian officials said on Friday, as Kyiv's forces fell back in the face of Moscow's biggest advance for weeks.
Ukraine said its forces still held new defensive lines in the eastern Donbas region, despite apparent Russian advances on two major fronts there that showed how momentum has shifted in recent days.
Moscow's separatist proxies said they were in full control of Lyman, which Russia has attacked from the north in one major axes of its advance.
"I'm afraid that (President Vladimir) Putin, at great cost to himself and to the Russian military, is continuing to chew through ground in Donbas," British Prime Minister Boris Johnson told Bloomberg UK.
Ukrainian officials acknowledged that Russia had captured most of the town. But the defense ministry said forces were still blocking the Russians from launching an advance towards Sloviansk, a major city a half-hour drive further southwest.
To the east, Russian forces had encircled two-thirds of Sievierodonetsk and destroyed 90% of its buildings, regional governor Serhiy Gaidai said. It is the biggest city held by Ukraine in the Donbas. Russia has been trying to trap Ukrainian forces there and in Lysychansk on the opposite river bank.
Ukrainian presidential adviser Oleskiy Arestovych said overnight that Lyman had fallen, and that the well-organized Russian attack there showed Moscow's military was improving its tactics and operations.
After being driven back from the capital Kyiv in March and the outskirts of Ukraine's second city Kharkiv this month, Russian forces are staging their strongest advance in weeks in the Donbas.
The advance gained ground after Russian forces pierced Ukrainian lines south of Sievierodonetsk in the city of Popasna last week.
Popasna, reached by Reuters journalists in Russian-held territory on Thursday, was a wasteland of burnt-out buildings. With Russian tanks and military vehicles in the streets and attack helicopters low overhead, the bloated body of a dead man in combat uniform lay in a courtyard.
Tired of sheltering in a cellar, Natalia Kovalenko had returned to live in the wreckage of her flat. The balcony had been blown away and windows blasted out.
She stared into the courtyard, recounting how two people had been killed there and eight wounded by a shell when they went outside to cook. Inside, her kitchen and living room were filled with rubble, but she had tidied a small bedroom to sleep.
"I just have to fix the window somehow. The wind is still bad," she said. "We are tired of being so scared."
Russian ground forces have now captured several villages northwest of Popasna, Britain's Ministry of Defence said.
'What price'
Russia's advance in the east follows a Ukrainian counter-offensive that pushed Russian forces back from Kharkiv in May. But Ukrainian forces have been unable to attack Russian supply lines to the Donbas.
On Thursday, Russian forces shelled parts of Kharkiv for the first time in days. Local authorities said nine people were killed. Reuters filmed shells bursting in a neighborhood, sending clouds of smoke into the sky above a bloodstained pavement littered with broken glass.
The Kremlin denies targeting civilians.
In the south, where Moscow has seized a swathe of territory since the Feb. 24 invasion, Ukrainian officials believe Russia aims to impose permanent rule.
The Ukrainian military's southern command said Russia was shipping in military equipment from Crimea, building a third line of defense to prepare for a potential Ukrainian counter-attack, and mining the banks of a reservoir behind a dam on the Dnipro River that separates the forces.
"All this indicates that Russia will try to keep the occupied territories under its control," it said.
On the diplomatic front, European Union officials said a deal might be reached by Sunday to ban deliveries of Russian oil by sea, accounting for about 75% of the bloc's supply, but not by pipeline, a compromise to win over Hungary and unblock new sanctions.
In an overnight address, Zelenskiy criticized the EU for dithering over a ban on Russian energy imports, saying the bloc was funding Moscow's war effort with a billion euros a day.
"Every day of procrastination ... merely means more Ukrainians being killed," he said.
Western countries led by the United States have provided Ukraine with long-range weaponry, including M777 howitzers. Kyiv says it wants longer-range ground weapons, especially rocket launchers, to help it win artillery battles.
US officials say the Biden administration is considering supplying Kyiv with the M142 High Mobility Artillery Rocket System (HIMARS), which have a range of hundreds of kilometers (miles).
Washington had held back from supplying such arms, partly to avoid an escalation should Ukraine hit targets deep within Russia. US and diplomatic officials told Reuters Washington has discussed this with Kyiv.
"We have concerns about escalation and yet still do not want to put geographic limits or tie their hands too much with the stuff we're giving them," said one US official on condition of anonymity.
Russian Foreign Minister Sergei Lavrov said any supplies of weapons that could reach Russian territory would be "a serious step towards unacceptable escalation".
Russia calls its invasion of Ukraine a "special military operation" to defeat "Nazis" there. The West describes this as a baseless justification for a war of aggression.