Five missiles have reportedly struck Lviv, according to the city’s mayor.

“5 aimed missile strikes on Lviv,” Andriy Sadovy said in an update over his official Telegram account this morning, adding that authorities are seeking more detailed information.

Presidential adviser, Mykhailo Podolyak, added: “Five powerful missile strikes on the civilian infrastructure of ancient European Lviv. The Russians continue to barbarically attack Ukrainian cities from the air, cynically declaring to the whole world their ‘right’ ... to kill Ukrainians.”

Defenders of the besieged city of Mariupol will fight to the end against Russian forces, Ukrainian Prime Minister Denys Shmyhal says.

The port city has not fallen despite an ultimatum from Moscow to remaining fighters to give up, he said.

Ukraine's Foreign Minister Dmytro Kuleba said Russia has chosen to raze Mariupol to the ground.

Local officials said Russian forces have announced they will stop anyone from entering or leaving the city.

Capturing the whole of the city is seen as a major strategic prize for Russia, leaving it in control of a vast swathe of southern and eastern Ukraine.

An advisor to the mayor of Mariupol said residents would be forced to queue for a pass to enable them to move between districts and some could have their phones confiscated or be taken against their will to Russia.

In an interview with the US network ABC, Mr Shmyhal said a Russian deadline for Ukrainian forces in Mariupol to surrender by Sunday had been ignored.

"The city still has not fallen," he said. "There is still our military forces, our soldiers, so they will fight until the end. And as for now, they still are in Mariupol."