A total of 121 children have been killed in Russia's ongoing war against Ukraine as of Wednesday, according to Ukrainian officials.

Also, more than 167 children have been injured in the conflict since it began late last month, the Prosecutor General's Office said on Telegram.

Russian shelling damaged 548 educational institutions, 72 of which were completely destroyed, it added.

At least 953 civilians have been killed during the war and 1,557 injured, according to a tally by the UN.

The international body warns, however, that the true toll is "considerably higher."

More than 3.5 million people have fled Ukraine amid the Russian attacks, according to the UN refugee agency.