German Chancellor Angela Merkel as well as several other prime ministers including France's Francois Fillon, Italy's Silvio Berlusconi, Julia Tymoshenko of Ukraine and Fredrik Reinfeldt of Sweden, whose country currently holding the European Union's rotating presidency, are among those due to attend.
Poles will be paying close attention to what Russia's Putin will say Tuesday after a string of Russian publications and a film justifying the August 23, 1939, Nazi-Soviet Non-Aggression Treaty, known as the Molotov-Ribbentrop pact, which led to the partition of Poland between Germany and the Soviet Union.
On the sidelines of the ceremonies, the Russian premier is scheduled to hold a series of bilateral meetings, notably with his Polish counterpart Donald Tusk and Ukraine's Tymoshenko.
Aside from differences over history, issues such as energy and the possible US deployment of an anti-missile shield on Polish soil are likely to be on the agenda of the Polish and Russian leaders' talks.
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