Ukraine delivered its response to the latest US-drafted peace proposal aimed at ending the war with Russia to the Trump administration on Wednesday, US and Ukrainian officials told CNN, as the contours of a tenuous potential deal take shape and the US president continues to make clear he wants the conflict resolved quickly.

Ukraine said Thursday its long-range drones had struck a major offshore oil platform in the Caspian Sea this week, signalling an expansion of its target list in a mounting campaign to cut off Russian energy revenues funding its war.