Poland scrambled fighter jets on Monday morning to secure its airspace after neighbouring western Ukraine was hit by major Russian strikes.

'Due to the intensive air attack by the Russian Federation on the territory of Ukraine, Polish and allied aircraft began to operate in Polish airspace in the morning,' Warsaw's Operational Command said in a statement on social media.

Russia struck deep beyond the frontlines overnight, hitting western Ukraine with dozens of drones and missiles, according to Mayor of Rivne Oleksandr Tretyak, who called it 'the largest attack' on the region.

Moscow's Tu-22M3 and Tu-95MS strategic bombers akin to those destroyed last week in Ukraine's 'Operation Spiderweb' were deployed to strike Dubny airbase near Rivne.

Russian pilots also unleashed lethal air-launched Kinzhal hypersonic missiles from MiG-31 jets, while other reports said four Kh-22 missiles from Tu-22M3 missile carriers slammed into strategic Snake Island in the Black Sea.