Russian strikes on Ukraine -- including in Kyiv -- killed eight people, Ukrainian authorities said Sunday, a day after Moscow vowed to achieve its war aims "no matter the circumstances."

Russia has stepped up attacks on Ukraine's capital in the fifth year of its invasion, as the country braces for another winter of war, with Ukraine charging that Moscow is deliberately hitting civilian targets.

Interior Minister Ivan Vyhivskyi announced the latest deaths on Sunday afternoon, saying Russian strikes had hit a children's centre in the northern city of Sumy, killing three people including a 16-year-old girl.

Earlier, President Volodymyr Zelensky said three people had been killed in night-time strikes on the southern Zaporizhzhia region and a Russian drone strike had killed one man in Kyiv.

Kyiv Mayor Vitalii Klitschko said a woman and two 16-year-olds had also been wounded and hospitalised in the capital.

"The enemy continues to relentlessly attack the Kyiv region with strike drones," the city's administration said.

"Sixteen sites have been damaged," including 12 private houses in Kyiv's outskirts, as well as a warehouse and production facility, it added.

And authorities in the Odesa region said a "massive strike" on the south of the Black Sea region had killed one more person.

Russian strikes damaged housing, a shop, a hotel, a medical building and a warehouse storing grain, said regional head Oleg Kiper.

"This past week, the Russians launched more than 2,200 attack drones against Ukraine, as well as around 1,650 aerial bombs and 38 missiles of various types, a significant number of them ballistic missiles," Zelensky posted Sunday on social media.

The strikes had targeted housing "and other civilian infrastructure" in various parts of the country, he added.

On Saturday, Russian Foreign Minister Sergei Lavrov told the UN Moscow intended to continue its military campaign "to the end".

Russia denies charges that it aims for civilian targets.

In Moscow, the defence ministry said Sunday that Russian forces had seized the border village of Khrypuny in Ukraine's eastern Kharkiv region, where Russia controls pockets of land. 

Russia does not claim the Kharkiv region as its own -- unlike the Donetsk, Lugansk, Zaporizhzhia and Kherson region. Throughout the war however, it has attacked the region and seized land there. 

The Kremlin has repeatedly said it intends to seize the rest of east Ukraine.

US-led talks to end the war, launched by the Kremlin in 2022, have failed to lead to a breakthrough, with the UN warning of a rise in civilian deaths.

© Agence France-Presse