It also comes at an inauspicious time for the Trump administration, which deployed its top negotiator, U.S. Envoy for the Middle East Steve Witkoff, to hold his third round of face-to-face talks with Putin approximately 48 hours before the strike.

The missile attack on Sumy on April 13 served as a grim reminder of the deadly cost of Russian dictator Vladimir Putin’s invasion of Ukraine — and highlighted how little progress Trump has made in ending a war he once claimed he could stop quickly.

President Donald Trump reacted to a Russian attack that killed 34 people in the Ukrainian city of Sumy on Sunday, saying he was told Russia "made a mistake"

The fronts have hardened in the war in Ukraine following the rocket attack on Sumy. The EU plans to send more arms to Kyiv, while the US has extended sanctions on Russia. Trump says he has new proposals to end the war.

Ukraine's Air Force said a new Russian missile and guided bombs targeted the city of Sumy in northeastern Ukraine on Monday evening, a day after a missile strike killed 35 people in the city.