Besides calling on the Western leaders to impose a no-fly zone, Zelensky shared footage apparently from inside the Mariupol hospital, which appeared badly damaged.

"Mariupol. Direct strike of Russian troops at the maternity hospital. People, children are under the wreckage," the Ukrainian President wrote on Twitter.

"Atrocity! How much longer will the world be an accomplice ignoring terror? Close the sky right now! Stop the killings! You have power but you seem to be losing humanity," he added.

Local authorities told the Ukrainian media that at least 17 people, including children, women in labour and staff, have been wounded in the air strike.

Ukrainian MP Dmitry Gurin had initially told BBC that there were “a lot of dead and wounded women” in the hospital building, but, later Donetsk military administration chairman Pavel Kirilenko said there were no casualties among mothers and children.

Local media reported that at least 17 people, mainly medical staff, were wounded.

Mariupol, a strategic port city in southern Ukraine, has been under heavy attack since Russia began the invasion.

According to the Mariupol mayor's office, over 1,000 civilians have been killed so far in the shelling by the Russian forces.