The Russian leader has met four times in as many months with Trump envoy Steve Witkoff and continued to reject the U.S. proposal for ending the three-year war, which would freeze the conflict along the current battle lines and thus give Russia significant territorial gains.

Ukrainian executive champions the U.S. minerals deal as a way to open Kyiv to private investment and expand energy security that has been a chief target in Russia's war.

He alleged that after a first wave of strikes, Ukraine had sent more drones to try to "finish off the survivors". Another Russian official, quoted by state media, alleged that Ukrainian forces used cluster munitions against ambulances gathering at the scene.

Ukraine's President Volodymyr Zelensky accused Russia of more than 100 drone attacks overnight into April 30 and injuring dozens of people, including children. Zelensky said two waves of strikes on Kharkiv on "13 civilian locations" injured 45 people,