Ukraine’s President Volodymyr Zelensky has said Russia has launched an assault to seize the eastern Donbas region.
Moscow bombarded cities with rocket and artillery fire on Monday and in a video address Mr Zelensky said that the battle “for the Donbas has begun”.
Ukraine’s top security official, Oleksiy Danilov, said that Russia tried to break through the Ukrainian front lines in the region.
The offensive has been long-expected after Russia failed to seize Kyiv.
Russia initially appeared to want to capture major Ukrainian cities and topple the government.
But after facing stiff resistance, Russian defence officials said that its main objectives in the “first stage of the operation” had been “generally accomplished” and its forces were moved from areas around the capital.
They announced plans to redirect the focus of the invasion towards the “liberation” of the Russian speaking Donbas region.
Russia’s President Vladmir Putin has portrayed the invasion as an attempt to demilitarise and “denazify” Ukraine, something Ukraine and its allies dismiss as a ruse for an unprovoked attack.
Throughout Monday, Russia unleashed a barrage of rocket and artillery fire on a number of eastern areas, with eight civilians killed in the city of Kreminna in Luhansk and in the Donetsk area.
Seven people were killed and 11 more were injured in four Russian strikes in Lviv, a western city that has largely been spared the attacks seen elsewhere in Ukraine.