A number of explosions shook parts of Kyiv early on Sunday in the first assault on Ukraine’s capital for weeks.
Columns of black smoke could be seen above the city – Russia says it hit tanks supplied by European countries. At least one person was reported hurt.
The city has been largely spared in recent months as Russian forces concentrate attacks in the Donbas region of eastern Ukraine.
Some of the fiercest fighting is currently in the city of Severodonetsk.
Ukraine’s President Volodymyr Zelensky said the situation there remained “extremely difficult” with fighting being waged street by street.
Capturing the city would deliver the Luhansk region to Russian forces and their local separatist allies, who also control much of neighbouring Donetsk.
Severodonetsk and other cities in the eastern regions were being hit by “constant air strikes, artillery and missile fire” but Ukrainian forces were holding their ground, Mr Zelensky said.
On Saturday, Luhansk’s governor said Ukrainian forces were still holding on to Severodonetsk but were awaiting precision weapons donated by Western allies.
“As soon as we have enough Western long-range weapons, we will push their artillery away from our positions. And then, believe me, the Russian infantry, they will just run,” Serhiy Haidai said.
The fighting has now left most of Severodonetsk in ruins, but thousands of civilians are still sheltering in basements there.
Governor Haidai said Russian forces were blowing up bridges on the river to prevent Ukraine bringing in military reinforcements and delivering aid to civilians.
Tens of thousands of people have been killed and millions forced to flee their homes since Russia launched an invasion of Ukraine in late February, despite diplomatic efforts to bring about a ceasefire.
But correspondents say that life in the capital has started to feel almost normal.
The thick black plumes of smoke rising over Kyiv as it awoke this morning were however a stark reminder this is a city still at war, the BBC’s Joe Inwood says.
Kyiv’s Mayor Vitali Kiltchko said the explosions had taken place just to the west of the centre – in the Darnytskyi and Dniprovskyi districts.
Russia’s defence ministry said it had used long-range high-precision missiles to target tanks supplied by Eastern European countries.
In other developments:
France’s President Emmanuel Macron provoked anger from Kyiv after suggesting that Ukraine and the West should avoid humiliating Russia in the war
The Russian military said it had shot down a Ukrainian military transport plane carrying weapons near the Black Sea port of Odesa on Saturday
Russia continued heavy shelling of Mykolaiv, a key port city on the approaches to Odesa – the BBC’s Laura Bicker met shaken but determined civilians there
A major fire engulfed a wooden church at the Sviatohirsk Lavra Monastery in Donetsk region; Ukraine blamed Russian shelling, which Russia denied, instead blaming it on retreating Ukrainian troops.(BBC)