MOSCOW/KYIV－The Russian military on Saturday announced that it had taken full control of Severodonetsk, the administrative center of the Ukrainian-controlled part of the eastern Lugansk region.

With the support of Russian troops, the forces of Lugansk launched "a successful offensive "and "completely liberated" the cities of Severodonetsk and Borovskoye as well as two settlements in Lugansk, Russian Defense Ministry spokesman Igor Konashenkov told a briefing.

Severodonetsk Mayor Oleksandr Stryuk was reported by the Ukrainian government-run Ukrinform news agency as saying: "The city is already completely occupied by the Russian Federation. They are trying to establish their order."

Civilians who had been sheltering at the Azot chemical plant had begun to leave, said Stryuk, adding that there was enough medicine in the city to give them emergency assistance.

Commenting on the development, Ukrainian President Volodymyr Zelensky on Saturday said Ukraine would win back all the cities it had lost to Russia, including Severodonetsk, and admitted the conflict was becoming tough to handle.

In a late-night video address, he also said Ukraine had been hit by 45 Russian missiles and rockets over the prior 24 hours, in an action that he described as a cynical but doomed attempt to break his people's spirits.

"Therefore all our cities, Severodonetsk, Donetsk, Lugansk, we'll get them all back," he said.

A day after the key eastern city fell to Russia in a major setback for Ukraine, Russian missiles struck the Ukrainian capital Kyiv on Sunday.

The missiles hit Kyiv's central Shevchenkivskiy district on Sunday morning, partially destroying a nine-story apartment building and causing a fire, the city's mayor Vitali Klitschko said on the Telegram messaging app.

The latest developments on the battlefield come as world leaders gathered in Europe to discuss further sanctions against Moscow.

Before a G7 meeting in Germany, British Prime Minister Boris Johnson said that Britain is ready to guarantee a further $525 million of World Bank loans to Ukraine later this year, taking total fiscal support this year to $1.5 billion.

"Ukraine can win and it will win. But they need our backing to do so. Now is not the time to give up on Ukraine."

In St. Petersburg on Saturday, Russian President Vladimir Putin said Russia would deliver Iskander-M missiles capable of carrying nuclear warheads to Belarus in the coming months, as he received Belarusian leader Alexander Lukashenko.

He also offered to upgrade Belarus' warplanes to make them capable of carrying nuclear weapons, in comments broadcast on Russian television.

Xinhua - Agencies