Jacek Siewiera, head of Poland's National Security Bureau (BBN), said this during the Warsaw Security Forum, according to an Ukrinform correspondent.
"First of all, we must support the Ukrainians until their victory, as they see it," Siewiera said.
According to him, Russian aggression against Ukraine is entering a "new phase of a protracted war of attrition." After one-and-a-half years of intense fighting, the war is far from over.
Siewiera said that Russia had not achieved its strategic goals, but is determined to continue the war at any cost.
"You should not expect that Ukrainians will fight the way the West would fight: they know what victory means to them and what the price of defeat will be. Whichever option they choose to conduct hostilities, and if it is to bring results, the West must continue to support it. I assure you that Poland will continue to do so," he said.
According to him, Western countries should support Ukraine and Ukrainian society in all aspects of its functioning.
"This support is extremely important because this war probably won't end either this year or next year," Siewiera said.