Paweł Soloch made the comment in an interview with private broadcaster Polsat on Monday, Polish state news agency PAP reported.
Asked about the war in Ukraine, Soloch, who heads President Andrzej Duda’s National Security Bureau (BBN), said: “Russia is not giving up its attempt to conquer Ukraine. It may last years.”
Soloch added that "the present situation slightly resembles the 17th century when the czarist empire was conquering Ukraine and later the Crimean Khanate; these wars continued for years.”
He stated: “I believe that this is the approach of the Russian elites: ‘If we can’t conquer all of Ukraine in the current campaign, then we'll make mincemeat of it one piece at a time.’”
According to Soloch, Russia is preparing referenda in occupied parts of Ukraine to officially annex these territories so that “attempts to retake them can be treated as an attack on Russia.”
“This increases the threat that weapons of mass destruction will be used, such as nuclear arms,” he added.
Soloch cautioned that “this is all speculation, but one can see a certain consistency in the Russian policy.”
'The next two months could prove decisive'
He noted that Russia was making some “slow gains” in the Luhansk and Donestsk Oblasts that make up Ukraine’s eastern Donbas region.
Meanwhile, Ukraine "is slowly retaking villages” in the south of the country, “but this is not an offensive,” he said.
According to Soloch, "a successful Ukrainian offensive would create the basis for peace talks, or at least ceasefire talks.”
He stated: “Indeed it looks as though the next two months could prove decisive. Will Ukraine mount an offensive?”
He concluded: “By October there should be some decisive developments. Whether they will happen, time will tell."
Monday was day 166 of the Russian invasion of Ukraine.
Source: PAP, bbn.gov.pl