Ukrainian President Volodymyr Zelenskyy is urging greater international pressure on Moscow following a deadly Russian missile strike that hit a Kyiv apartment building this week, killing 23 people.

It was the deadliest attack on the Ukrainian capital in almost a year, and came as Moscow has intensified air assaults on the city.

An American citizen was among at least 28 people killed in a deadly and huge Russian strike on Kyiv overnight Tuesday.