Polish and allied aircraft were activated on Monday to ensure the safety of Polish airspace after Russia launched missiles strikes targeting western Ukraine, near the border with the Poland, the Operational Command of the Polish armed forces said.

Russia has launched overnight attacks on four Ukrainian cities, injuring at least 15 people and targeting energy infrastructure.

Russia launched yet another attack on Ukraine overnight, with more than 300 drones and seven missiles, according to Ukraine's air force. While most of the barrage was intercepted, the relentless attacks prompted President Trump to give his Russian counterpart an ultimatum.