Polish Prime Minister Mateusz Morawiecki said on Sunday that Hitler's Germany was responsible for the Holocaust, not the Nazis.
His comments, quoted by AFP, were made at an official ceremony marking 74 years since the liberation of the Auschwitz-Birkenau death camp.
"Hitler's Germany fed on fascist ideology... But all the evil came from this (German) state and we cannot forget that, because otherwise we relativize evil," he was quoted as having said.
"The Polish state acts as the guardian of the truth, which must not be relativized in any way," he added.
"I want to make a promise here to (preserve) the complete truth about that era," he added, in a speech in the southern city of Oswiecim to mark Holocaust Memorial Day.
Sunday's ceremony at Auschwitz was attended by a number of former prisoners at the camp.
Polish far-right nationalists demonstrated during the ceremony, protesting the emphasis on the Jews killed at Auschwitz and not the Poles killed by the Nazis.
Morawiecki's speech comes after last year's row over a Polish law that made it illegal to accuse the Polish nation or state of complicity in Nazi German crimes.
Poland subsequently changed the legislation to remove fines and jail terms of up to three years for anyone found guilty of ascribing Nazi crimes to the Polish nation or state.
Morawiecki appeared in his remarks to be responding to an idea often mentioned in Poland, which claims that historians try to attribute responsibility for the genocide of Jews exclusively to the Nazis, without recalling the role played by the German state and Germans as a nation.
Auschwitz-Birkenau was set up by Nazi Germany in occupied Poland. With one million Jews killed there between 1940 to 1945, the camp has become a symbol of Nazi Germany's genocide of the European Jews.
More than 100,000 other people including non-Jewish Poles, Roma, Soviet prisoners of war and anti-Nazi resistance fighters also perished there.