President Volodymyr Zelensky vowed there would be no let-up in Ukraine's fight to regain its territory as Kyiv said its troops had crossed a major river, paving the way for an assault on Russia's occupation forces in the eastern Donbas region.

Ukrainian troops "have pushed across the Oskil. From yesterday, Ukraine controls the east bank", the Ukrainian Armed Forces wrote on Telegram late on Sunday.

Video/Photo: Reuters