The military governor of Ukraine’s eastern region of Luhansk said fighting on June 20 along the entire front line was “extremely difficult” as President Volodymyr Zelensky said that Russia is “very nervous” about the approaching decision of the European Council on granting Ukraine candidate status for EU membership.

Zelensky has 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 a 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 and 24.

One of Russian President Vladimir Putin’s goals, when he sent Russian forces into Ukraine in February, was to prevent Ukraine’s integration into institutions such as the EU. Putin now says he has “nothing against” EU membership for Ukraine, although a Kremlin spokesperson said Moscow was closely following the bid in part because of recent cooperation in the area of defence among EU members.

Zelenskyy 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,” Zelensky said. “The occupiers are receiving answers to their actions against us.”

Ukrainian forces are defending Lysychansk and Syevyerodonetsk, where the most difficult fighting is taking place, said Serhiy Hayday, whose Luhansk region has been the scene of the heaviest fighting in recent weeks.

Hayday said on national television that Russian forces control 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 shell fire.

“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.

Even so, the Russians had yet to complete an encirclement of Ukrainian forces, who were inflicting “significant losses” on them, he said.

Russia-backed separatists in Luhansk claimed to have captured Toshkivka, a town south of Syevyerodonetsk on the mostly Ukrainian-held western bank of the Siverskiy Donets river.

Hayday earlier acknowledged a Russian attack on Toshkivka had “had a degree of success” and said Russian forces were also seeking a foothold near Ustinovka, a village further north along the river. He confirmed Russia’s claim to have captured Metyolkine.

Air strikes in the region around the southern Ukrainian port city of Odesa on June 20 caused injuries and damaged infrastructure, the head of the regional military administration said.

A series of Russian missile strikes were launched in the region overnight and during the day, Maksym Marchenko said on Telegram.

A spokesman for the Odesa regional military administration said earlier that Ukrainian air defence forces had shot down Russian missiles.

A Russian missile attack destroyed a food warehouse in the Ukrainian Black Sea port after a Russian official said three people were injured and seven more were missing after Ukraine forces fired on Black Sea drilling platforms off the coast of Crimea.

“We guarantee that the search will continue,” said Sergei Aksyonov, the Moscow-appointed governor of Crimea, on Telegram. He also said that 94 people had been evacuated from drilling rigs in the Black Sea after the strike.

Early on June 20, the Ukrainian General Staff said the Russian side had deployed an S-300V4 anti-aircraft missile division in its western region of Bryansk near the Ukrainian border.

The governor of Bryansk said the border village of Suzemka had been shelled from northern Ukraine, injuring one person and damaging a power station.

The Kremlin 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 acknowledgement 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 caught fighting for Ukraine.

With reporting by Reuters, TASS, and AFP