A Russian missile attack has killed at least seven people and injured another 22 - including a child - in Ukraine's southern city of Zaporizhzhia, local officials say.

As many as five people may still be trapped under rubble after Tuesday's strike on a private clinic and residential buildings in the city centre, police say.

Overnight, rescuers pulled out two women from the wreckage. They are now being treated in hospital. A search and rescue operation is continuing.

Zaporizhzhia regional head Ivan Fedorov says Russia fired a ballistic missile, most likely an Iskander. Russia's defence ministry has not commented.

Expressing condolences to the victims' relatives, Fedorov also vowed that Russia would pay for "every Ukrainian life taken and mutilated".

"We will not forgive!" he said.

A day of mourning has been declared in the Zaporizhzhia region on Wednesday.

Ukraine has repeatedly asked its Western allies to provide more advanced air defence systems to repel almost daily Russian missile and drone attacks.

Shortly after the Zaporizhzhia attack, President Volodymyr Zelensky reiterated that plea.

"We don't have enough systems to protect our country from Russian missiles. But our partners have these systems. Again and again, we repeat that air defence systems should save lives, not gather dust in warehouses," he said.