Russia's defence ministry said Monday that it had downed 251 Ukrainian drones overnight, in one of Kyiv's largest retaliatory attacks on its neighbour since Moscow invaded over three years ago. "Over the past night, air defence alert systems intercepted and destroyed 251 Ukrainian fixed-wing unmanned aerial vehicles," the ministry wrote on Telegram.

It said Russian forces downed 40 drones over Crimea, annexed by Russia in 2014, as well as 62 over the Black Sea. Dozens more were shot out of the skies over the Kursk and Belgorod regions, as well as others, the ministry said.

Russia has kept up a near-constant barrage of drone and missile attacks, particularly on Ukraine's energy networks, as it grinds on with the full-scale invasion it launched in February 2022. Ukraine has increasingly responded with its own strikes targeting Russian oil refineries and other energy infrastructure.