Ukraine has said that Russian forces surrounding the southern port city of Mariupol have destroyed a maternity hospital.

President Volodymyr Zelensky said children were under the wreckage and called on Western leaders to impose a no-fly zone, the BBC reported.

He also posted footage apparently from inside the hospital, which appears badly damaged.

There is no information yet on casualties, or who was inside the hospital at the time.

The Mariupol city council said the strike had caused "colossal damage", and published footage showing burned-out buildings, destroyed cars, and a huge crater outside the hospital.

Mariupol has been surrounded by Russian forces for several days, and repeated attempts at a ceasefire to allow civilians to leave have broken down.

Crisis in Ukraine
Crisis in UkraineIANS

"The whole city remains without electricity, water, food, whatever and people are dying because of dehydration," Olena Stokoz of Ukraine's Red Cross told the BBC, adding that her organization would continue trying to organize an evacuation corridor.

Ukraine russia war

Earlier Ukrainian Foreign Minister Dmytro Kuleba said "almost 3,000 newborn babies lack medicine and food" in Mariupol, and that Russia continued to hold more than 400,000 people "hostage".

Russia insists that it does not target civilian infrastructure in Ukraine.