KYIV, March 22 (AFP) - President Volodymyr Zelenskyy said on Wednesday (Mar 22) that he visited military positions near the frontline town of Bakhmut in eastern Ukraine, as a Russian strike battered a residential building, injuring dozens.

At least one person was killed and 32 more injured in the block of flats in Zaporizhzhia, a city near the frontline, just before Zelenskyy announced his visit to the front, the mayor said.

And officials announced the death toll from a separate overnight drone attack by Russia on a school south of the capital Kyiv had risen to seven, with another nine injured.

During the visit to the front near Bakhmut - the longest and bloodiest battle of Russia's invasion - Zelenskyy recognised the troops had a "difficult" task.

"I am honoured to be here today to award our heroes. To shake hands and thank them for protecting the sovereignty of our country."

Video released by Zelenskyy's office showed him meeting servicemen in a warehouse and handing out state decorations.

Russian and Ukrainian forces have invested heavily in the battle for Bakhmut, even though analysts say the city carries little strategic value.

Kyiv says the battle for the industrial town, which had a pre-war population of around 80,000 people, is key to holding back Russian forces along the entire eastern front.

As the battle grinds on, the International Criminal Court rejected threats reportedly made against the court by a key ally of President Vladimir Putin after it issued a war crime warrant against the Russian leader.

Former Russian president Dmitry Medvedev reportedly talked about targeting The Hague, where the court is based, with a hypersonic missile as a reprisal for the Putin warrant, according to Dutch media.

The presidency of the Assembly of States Parties, which groups the ICC's 123 member countries, said it "regrets these attempts to hinder international efforts to ensure accountability for acts that are prohibited under general international law".