Polish officials say a claim by the Russian ambassador that Warsaw was partly to blame for World War II has damaged bilateral relations.
Russian Ambassador to Poland Sergei Andreev said on September 25 that Warsaw had blocked "the creation of an anti-Nazi coalition" which made Poland "co-responsible for World War II."
Andreev also justified the Soviet invasion of Poland during World War II as necessary to "guarantee the security of the Soviet Union."
The comments caused outrage in Poland.
The Polish Foreign Ministry said on September 26 that "the narrative presented by the highest official representative of the Russian state in Poland challenges historical truth and invokes some of the most mendacious interpretations of events, as resorted to during Stalinist and Communist years."
Andreev has been summoned to report to the Foreign Ministry on September 28.
Up to 6 million Poles -- more than 3 million of them Jews -- were killed in World War II, more than one-sixth of the country's prewar population.
Polish Prime Minister Ewa Kopacz said "the role of an ambassador accredited in a country should be to build to build harmony and friendly relations between countries."