A Russian drone and missile barrage has killed 25 people, including two children, in a western Ukrainian city, around 200 kilometres from the Polish border.

A drone has struck a Turkish-flagged tanker in Ukraine's Odesa region and set it ablaze. Monday's strike at Izmail port came a day after Ukrainian President Volodymyr Zelenskyy signed a deal to import U.

Another 40 people were wounded in the overnight strikes on Ukraine that targeted energy and transport infrastructure, forcing emergency power cuts in a number of regions.

Russia fired 476 strike and decoy drones, as well as 48 missiles of various types, at Ukrainian targets overnight, Ukraine’s air force said.

As winter looms and Russian forces adapt their tactics, Ukrainian troops need to double down on technological innovation and flood the front line with more drones to halt Moscow's territorial gains, a senior commander said.

Russia is now using fiber-optic drones with a 50-kilometer reach, a senior Ukrainian official told Business Insider.