War is a genuine threat, and Europe is unprepared, Poland's Tusk says.

Donald Tusk, the prime minister of Poland, has cautioned that, for the sake of the continent as a whole, Russia cannot destroy Ukraine since we are living in a "pre-war era".

"It's real and it started over two years ago," he continued, adding that war was "no longer a concept from the past."

His remarks were made in response to Russia's huge attack on Ukraine's energy infrastructure on Thursday.

Vladimir Putin, the president of Russia, declared this week that Moscow has "no aggressive intentions" against the nations of NATO.

He called it "complete nonsense" that his nation, which possesses one of the biggest nuclear arsenals in the world, would attack the Czech Republic, Poland, or the Baltic nations, all of which, unlike Ukraine, are members of NATO.

He made a sharp comment about European security, pointing out that Russia had launched its first hypersonic missile attack on Kiev throughout the day.