A Ukrainian pilot was killed and his F-16 fighter jet crashed as after Russia launched a huge aerial assault involving hundreds of drones and scores of missiles overnight, the Ukrainian military said on Sunday.

Russia launched the most extensive aerial bombardment of Ukraine since its full-scale invasion, according to Kyiv, signalling a sharp escalation in Moscow’s campaign and further undermining fragile hopes for a negotiated resolution to the war now in its fourth year.

Russia launched its biggest aerial attack against Ukraine overnight, a Ukrainian official said Sunday, part of an escalating bombing campaign that has further dashed hopes for a breakthrough to end the three-year-old war.