Poland has long warned the West of Russia’s apparent imperial ambitions, and argued that these ambitions may not be sated by defeating Ukraine.
"Putin has shown himself as a ruthless politician who will not stop at anything. If Kyiv falls, Russia will direct its aggression against Poland," Morawiecki wrote in an article in the Super Express newspaper.
The prime minister also described as an "unfortunate accident" the death of two people in a blast believed to have been caused by a stray Ukrainian surface to air missile.
Morawiecki said the sole responsibility for the incident lies with Russia.
"The death of two Poles has made us realise just how close the war is... bombs are falling near the Polish borders. The main cause (of the strike - PAP) is well known - it would never have happened if not for the war and the mass bombardment of Ukraine. Russia is solely responsible for this tragedy," Morawiecki wrote.
He also called for more support for Ukraine adding that this was "the only way to avoid a war with Russia." (PAP)