Andrzej Duda was speaking as he attended memorial ceremonies to mark 81 years since the Soviet Union invaded Poland from the east, shortly after Nazi Germany attacked from the west.
Speaking during a commemorative event in the village of Wytyczno in the east of the country, Duda said that Poland was in the opening phase of World War II struck by two military powers it could not defeat, Nazi Germany and Soviet Russia.
He paid tribute to soldiers who fought to defend Poland against the Red Army in September 1939.
"Today, Russian, and earlier Soviet, propaganda has been trying to portray that brutal act of Soviet aggression as an effort to protect residents in Belarus and Ukraine," he said.
"We all know perfectly well that this is not true," Duda added.
He noted that one consequence of the Soviet wartime aggression was the Katyn massacre of over 20,000 Polish officers.
Invaded by two military powers
At dawn on September 17, 1939, Soviet troops invaded Poland following a secret agreement with the German Third Reich.
Poland was then caught between German Nazi forces advancing from the west and Soviet forces from the east.
Following the invasion, some 250,000 Polish soldiers were captured by the Soviets, who later executed thousands of prisoners of war, public broadcaster Polish Radio’s IAR news agency has reported.
Mass deportations of the civilian population followed, with up to 1.5 million Poles transported away into the Soviet interior, mainly to Siberia and Kazakhstan, according to some estimates.
Tragic date in history
Officials including Poland's conservative leader Jarosław Kaczyński on Thursday attended ceremonies at sites such as Warsaw's Monument to the Fallen and Murdered in the East.
A special Independence Concert was scheduled to be held in the evening at the city's central Piłsudski Square.
As they marked the anniversary, officials said that September 17, 1939 was one of the most tragic dates in recent Polish history.
Tens of thousands of ethnic Poles killed in the former USSR before the 1939 Soviet invasion were remembered at memorial ceremonies in Warsaw last month.
Meanwhile, a crowd of demonstrators staged a rally outside the Russian embassy in Warsaw on Wednesday evening to commemorate Polish victims of Soviet crimes and warn the world over modern-day Russia.
(gs/pk)
Source: IAR, PAP, TVP Info, prezydent.pl