Russia stepped up airstrikes on Kyiv on Saturday, killing at least one person at a tank factory a day after Moscow warned it would renew attacks following two weeks of relative calm in the Ukrainian capital.

Kyiv mayor Vitali Klitschko said at least one person was killed and several wounded in the attack.

Smoke rose from the Darnyrsky district in the southeast of the capital after what Moscow said were “high-precision long-range” strikes on the armaments plant.

“Our forces are doing everything possible to protect us, but the enemy is insidious and ruthless,” Klitschko said.

“It’s no secret that a Russian general recently said they were ready for missile attacks on the capital of Ukraine. And, as we see, they are carrying out such shelling.”

A heavy police and military presence was deployed around the factory, the day after a similar strike on a plant that produced the Neptune missiles Kyiv and Washington say sunk Russia’s Black Sea naval flagship on Thursday.

Russia, which used sea-based long-range missiles to hit the Vizar plant on Friday, says the Moskva missile cruiser sank while being towed back to port after ammunition exploded on board.

Amid escalating tit-for-tat sanctions since President Vladimir Putin invaded Ukraine on February 24, Russia on Saturday said it was banning entry to British Prime Minister Boris Johnson and several other top UK officials.

“This step was taken as a response to London’s unbridled information and political campaign aimed at isolating Russia internationally, creating conditions for restricting our country and strangling the domestic economy,” the foreign ministry said in a statement.

The ministry accused London of “unprecedented hostile actions”, in particular referring to sanctions on Russia’s senior officials, and “pumping the Kyiv regime with lethal weapons”.

Sanctions

Britain has been part of an international effort to punish Russia with asset freezes, travel bans and economic sanctions, and Moscow’s new entry blacklist includes Deputy Prime Minister Dominic Raab, Foreign Secretary Liz Truss, and Defence Secretary Ben Wallace.

Saturday’s strike on the Ukrainian capital was among the first since invading Russian forces began withdrawing from regions around Kyiv last month, instead turning their focus on gaining control of the eastern Donbas region.

Kyiv regional governor Oleksandr Pavliuk said there were at least two other Russian strikes on the city Friday and that civilians thinking about returning should “wait for quieter times”.

Residential areas of Kyiv were struck repeatedly at the beginning of Russia’s invasion of Ukraine. Moscow has denied intentionally striking civilian infrastructure.

‘Big blow’

A Pentagon official said that the sinking of the Moskva, which had been leading Russia’s naval effort in the seven-week conflict, was a “big blow” for Moscow, while the fate of its crew of more than 500 was uncertain.

The official said survivors were observed being recovered by other Russian vessels, but Ukrainian authorities said bad weather had made rescue operations impossible.

Russia’s Black Sea fleet has been blockading the besieged port city of Mariupol, where Russian officials say they are in full control although Ukrainian fighters are still holed up in the city’s fortress-like steelworks.

The United States pledged a new $800-million military aid package for Ukraine this week, including helicopters, howitzers and armoured personnel carriers, and on Friday the German government said it plans to release more than a billion euros ($1.1 billion) in aid as well.

US media reported that Russia had sent a formal complaint to Washington about its support of Kyiv this week.

In the diplomatic note, Moscow warned the United States and NATO against sending the “most sensitive” weapons, saying such shipments were “adding fuel” to the situation and could come with “unpredictable consequences”, the Washington Post reported.

Focus on east

Ukrainian President Volodymyr Zelensky warned Friday that Russia might use nuclear weapons out of desperation as its invasion falters, echoing recent comments by CIA director William Burns.

“They could do it, I mean they can,” Zelensky told CNN. “For them, life of the people is nothing.”

Zelensky said on Friday that between 2,500 and 3,000 Ukrainian soldiers had been killed in the conflict so far, compared to 19,000-20,000 Russian dead.

He said that around 10,000 Ukrainian soldiers had been wounded, and that it was “difficult to say how many will survive”.

Russia has so far detained around 1,000 Ukrainian civilians and captured 700 soldiers, Ukraine’s Deputy Prime Minister Iryna Vereshchuk said, while Ukraine has captured around 700 Russian soldiers.

Nine humanitarian corridors were to be opened on Saturday to allow civilians to flee the fighting, including from Mariupol, the UNIAN news agency quoted her as saying.

At least 200 children have been killed in the Russian offensive and another 360 wounded, the public prosecutor said.

Russia’s military focus now seems to be on seizing the eastern Donbas region, where Russian-backed separatists control the Donetsk and Lugansk areas.

This would allow Moscow to create a southern corridor to the occupied Crimean peninsula, and Ukrainian authorities have been urging people in the region to quickly move west in advance of a large-scale Russian offensive.

Lugansk governor Serhiy Gaidai called Saturday for civilians to leave the area while they still can.

“Evacuate, while there’s still an opportunity,” he wrote on Telegram, warning that they might be used as human shields if they remain.