Smoke from artillery strikes rises over damaged buildings amid fighting in Toshkivka, in Ukraine's Luhansk region, on June 19.
Russian forces has continued to shell the Donbas as Ukrainian officials say the situation on the entire front line in the east is "extremely difficult" and President Volodymyr Zelenskiy warned that Moscow was "very nervous" about the approaching decision of the European Council on granting Ukraine candidate status for EU membership.
Ukrainian forces continue to defend Lysychansk and Syevyerodonetsk, where the most difficult fighting is taking place, said Luhansk military governor Serhiy Hayday.
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Hayday said on national television that Russian forces controlled most of Syevyerodonetsk but not the Azot chemical plant, where hundreds of civilians have been sheltering for weeks. He said the road connecting Syevyerodonetsk and Lysychansk to the city of Bakhmut was under constant shellfire.
"Lysychansk has been suffering from massive Russian shelling all day. It is impossible to establish the number of casualties as of yet," he said, adding that the shelling has been perhaps the heaviest the city had yet experienced. However, the Russians have failed so far to complete an encirclement of Ukrainian forces, who were inflicting "significant losses" on them, he said. While Russia has been concentrating its firepower on the Donbas, advanced Western weapons systems donated to Ukraine have begun to make their mark elsewhere on the front line, British military intelligence said in its daily bulletin on June 21. Ukrainian forces last week claimed their first successful use of Harpoon anti-ship missiles, the British Defense Ministry said on Twitter .
"The target of the attack was almost certainly the Russian naval tug Spasatel Vasily Bekh, which was delivering weapons and personnel to Snake Island in the northwestern Black Sea," it said, adding that Ukraine had largely neutralized Russia's ability to establish control in the northwestern Black Sea. In Ukraine's biggest Black Sea port, Odesa, which is blockaded by the Russian Navy, a Russian missile destroyed a food warehouse on June 20, Ukraine's military said. The leader of Moscow-annexed Crimea, Sergei Aksyonov, said on June 20 that three people were wounded and seven more missing after Ukrainian forces attacked oil drilling platforms in the Black Sea off the Crimean coast. The information could not be independently verified.
Zelenskiy, meanwhile, predicted Moscow would escalate attacks ahead of the EU summit later this week, and he was defiant again on June 20 in his evening address to the nation.
"Step by step we are going through a crucial week and we are doing everything every day so that no one has any doubts that Ukraine deserves” EU candidate status, he said. "We are proving every day that we are already part of united Europe." Ukraine applied for EU membership days after the Russian invasion began on February 24 and was followed by bids from nearby Moldova and Georgia in the face of the regional threat posed by Russia's unprovoked attack. Leaders of all 27 EU states will consider the three applications at a summit on June 23-24.
Zelenskiy said Russia "is very nervous about our activity" and again shelled the major cities Kharkiv and Odesa on June 20 and also continued its offensive in the Donbas region.
"This is an evil that can be appeased only on the battlefield," Zelenskiy said . "The occupiers are receiving answers to their actions against us."
The Kremlin, meanwhile, said two Americans detained in Ukraine earlier this month while they were fighting with Ukrainian forces were mercenaries not covered by the Geneva Conventions.
Kremlin spokesman Dmitry Peskov's comments were the first formal acknowledgment that the two men, identified in U.S. reports as Andy Huynh, 27, and Alexander Drueke, 39, were being held. He said they should take responsibility for their "crimes."
Western governments have said the men were fighting with Ukrainian military forces when they were captured and therefore should be treated as prisoners of war under the Geneva Conventions.
Earlier this month, two Britons and a Moroccan were sentenced to death by a separatist court after being captured while fighting for Ukraine.