Polish Prime Minister Donald Tusk will participate in the events commemorating the 70th anniversary of the Katyn massacre, Polish Foreign Minister Radoslaw Sikorski said on Wednesday.

Russian Prime Minister Vladimir Putin called Tusk earlier on Wednesday and invited him to this year's commemoration of the 1940 execution of several thousand Polish POWs, mainly officers and soldiers, in Katyn, western Russia, which is largely seen as a further step towards rebuilding relations between Poland and Russia.

Both premiers have played a decisive role in improving relations between the two countries, Sikorski said.

Putin moved to heal the rift over the massacre when he and other world leaders visited the former Communist-bloc state in September 2009 to mark the 70th anniversary of Nazi Germany's attack on Poland and the start of World War II.

The Soviet Union in 1990acknowledged the massacre, which was ordered by Joseph Stalin. Modern Russia recognized Soviet responsibility for the mass shooting, but has not classified it as a war crime or genocide, something Warsaw has demanded.

Russia has resisted attempts to challenge the Soviet role in World War II, in which 27 million Soviet citizens died, according to official figures. Poland and former Soviet countries such as Ukraine and the Baltic states view Stalin's Soviet Union as an aggressor during the war and have compared it to Nazi Germany.

WARSAW, February 3 (RIA Novosti)