The Prosecutor of the International Criminal Court (ICC) on Friday urged parties to the conflict in Ukraine not to use heavy, high-explosive weapons in populated areas, as the Russian military continued to bombard civilian homes and infrastructure.

Britain's Karim Khan stated, "If the attacks are deliberately directed against civilians, then this is a crime. If the attacks are deliberately directed against civilian objects, then this is a crime."

"I strongly urge the parties to the conflict to avoid the use of heavy explosive weapons in populated areas," the attorney general added in a statement.

Khan also stressed that he continues to follow the "extremely worrying" developments of hostilities.

"The events of recent days force me to stress once again that all participants in this conflict must strictly respect the applicable rules of international humanitarian law," he added.

Mariupol attack

An attack on a maternity and children's hospital in the southeastern Ukrainian city of Mariupol on Wednesday killed 3 people, including a girl, and sparked international condemnation.

The Prosecutor of the International Criminal Court opened an investigation into the situation in Ukraine last week, after receiving the green light from 39 countries that are parties to the International Criminal Court.

The prosecutor announced Friday that two additional countries, Japan and North Macedonia, had supported the investigation.

He also called on Karim Khan to share "any relevant information" about the situation with investigators via an online portal dedicated to the investigation.

The International Criminal Court, based in The Hague, was established in 2002 to try individuals who are being prosecuted, especially on charges of war crimes, crimes against humanity or acts of genocide.

Ukraine has not signed the Rome Statute, the founding treaty of the International Criminal Court, but in 2014 it officially recognized the court's jurisdiction over crimes committed on its territory.

As for Russia, in 2016 it withdrew its signature on the Rome Statute, which means that the court can only prosecute Russians if they are arrested on the territory of a country that recognizes its jurisdiction.