Ukrainian President Volodymyr Zelensky has condemned a "horrific" Russian ballistic missile attack on the northeastern Ukrainian city of Sumy on Sunday, after repeated warnings from Ukrainian officials that a fresh offensive on the area could be imminent.

A Russian ballistic missile strike on the northeastern Ukrainian city of Sumy killed at least 20 people on Sunday morning, the city's acting mayor said.

At least 32 people have been killed in a Russian missile strike on the Ukrainian city of Sumy on Sunday, officials said. Two ballistic missiles struck the heart of the city at around 10:15 a.m. as people gathered to celebrate Palm Sunday,