He said it was a Russian missile strike intended to "intimidate Ukrainians" ahead of a NATO summit in Madrid later this week.

Ukrainian Foreign Minister Dmytro Kuleba posted on Twitter a photo of an injured child being carried on a stretcher, saying she had been "sleeping peacefully in Kyiv until a Russian cruise missile blasted her home".

The "G7 summit must respond with more sanctions on Russia and more heavy arms for Ukraine," he said.

Ukrainian President Volodymyr Zelensky will address both the G7 and NATO gatherings.

At their meeting in the Bavarian Alps, the G7 allies will take stock of the effectiveness of sanctions imposed so far against Moscow, consider possible new aid for Kyiv, and begin turning their eye to longer-term reconstruction plans.

The summit opened with the announcement of a ban on imports of Russian gold and an appeal by US President Joe Biden for a unified approach, saying: "We have to stay together."

The European Union this past week offered a strong show of support when it granted Ukraine candidate status, although the path to membership is long.

'Fully occupied'

Russian forces sought to encircle Kyiv in the first few weeks after the February 24 invasion, but Sunday's attack was the first strike on the capital since early June.

But it was the third time since the invasion that this northwest neighborhood had been hit. A weapons factory nearby produces air-to-air and anti-tank rockets among others.

An AFP team said there was a fire on the top three floors of the building and its stairwell was completely destroyed.

Afterwards, residents gathered at the bottom of the building, many of them in tears. One woman was still wearing a bathrobe.

"I woke up at the first explosion, went to the balcony and saw missiles falling and heard a huge explosion -- everything vibrated," 38-year-old Yuri told AFP, declining to give his surname.

Edward Shkuta, who lives next door, said there had been four missiles since 6:30am.

A building "was directly hit on the top floors and I saw wounded people coming out".

In recent months, the fighting in Ukraine has focused on the eastern Donbas region, which has been partially under the control of pro-Moscow separatists since 2014.

The Russians made a strategic breakthrough Saturday when they took the industrial hub of Severodonetsk, the scene of weeks of fierce battles that have left it largely destroyed.

Severodonetsk's mayor said it had been "fully occupied" by Russian troops after Ukrainian forces retreated to better defend the neighboring city of Lysychansk.

Pro-Moscow separatists on Saturday said Russian troops and their allies had entered Lysychansk, which faces Severodonetsk on high ground across the Donets river.

Its capture would give Russia control of Donbas' entire Lugansk region.

Far from the primary battleground, meanwhile, Russian missiles were striking targets in northern and western Ukraine.

"More than 50 missiles of various types were fired: air, sea and ground-based," Ukraine's air force command said, noting the difficulty of intercepting Russian models such as the Iskander.

Pull in Belarus

In Saint Petersburg on Saturday, 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.

Putin has referred to nuclear weapons several times since the invasion, in what the West has seen as a warning to the West not to intervene.

Ukraine said it had come under "massive bombardment" Saturday morning from neighboring Belarus which, although a Russian ally, is not officially involved in the conflict.

Twenty rockets "fired from the territory of Belarus and from the air" targeted the village of Desna in the northern Chernigiv region, Ukraine's northern military command said.

"Today's strike is directly linked to Kremlin efforts to pull Belarus as a co-belligerent into the war in Ukraine," the Ukrainian intelligence service said.

'No heating in winter'

As in the southern port of Mariupol before it, the battle for Severodonetsk has devastated the city.

On Saturday, Severodonetsk Mayor Oleksandr Striuk said civilians had begun to evacuate the Azot chemical plant, where several hundred people had been hiding from shelling.

"These people have spent almost three months of their lives in basements, shelters," he said. "That's tough emotionally and physically."

They would now need medical and psychological support, he added.

In Russian-occupied Mariupol, meanwhile, residents face the prospect of a desperately cold winter, according to mayoral adviser Petro Andryushenko, who said local committees were being instructed to collect data on the need for firewood and coal.

"This is a direct signal and an acknowledgement of the obvious fact -- there will be no heating in winter," he said.

The city's Moscow-backed leadership could not even provide heat if they wanted to, given the "huge damage" to the pipeline that supplied the city with natural gas, Andryushenko added. - AFP