WARSAW, Poland - The U.S, German and Israeli ambassadors in Warsaw weighed in Monday against claims by Russian President Vladimir Putin that Poland bears part of the blame for the outbreak of World War II.

“Dear President Putin, Hitler and Stalin colluded to start WWII. That is a fact. Poland was a victim of this horrible conflict,” Ambassador Georgette Mosbacher said on Twitter in English and Polish.

The Russian Embassy countered with a tweet saying: ”Dear Ambassador, do you really think that you know about history any more than you do about diplomacy?“

World War II began on Sept. 1, 1939, when Nazi German troops invaded Poland. Two weeks later, the Soviet Red Army also attacked embattled Poland from the east, in what Poles still refer to as a “stab in the back.” Days earlier, Germany and Russia had signed a pact with a secret protocol to carve up Poland and the Baltic states between themselves. Some six million Poles lost their lives during the whole of WWII.

Recently, Putin has argued that collusion between Western powers and Adolf Hitler paved the way for World War II. He also cast Poland as an anti-Semitic country that welcomed Hitler’s plans to destroy Europe’s Jews.

German Ambassador Rolf Nikel and Israeli Ambassador Alexander Ben Zvi took a stand Monday to blame the war’s outbreak on the August 1939 Nazi-Soviet pact.

Polish historian Mariusz Wolos told the Onet portal that Putin is aiming at “creating discord between Poland and the U.S. and the international Jewish diaspora.”

He said Putin is trying to erase Stalin’s alliance with Hitler from history.

British historian Roger Moorehouse tweeted to say that Putin’s words “provoked a much better popular understanding of the pact’s true nefarious nature and significance.”

On Sunday, Polish Prime Minister Mateusz Morawiecki protested Putin’s comments, saying they are deliberate “lies” and arguing that Putin is trying to deflect attention from recent political failures by Russia.

Poland did not invite Putin to international ceremonies Sept.1 in Warsaw marking the 80th anniversary of the war’s outbreak. He is also not to attend Jan. 27 observances of the liberation of the Auschwitz-Birkenaudeath camp that Nazi Germany operated in occupied Poland.

Relations between Russia and Poland have been tense since Poland threw off Moscow-controlled communist rule 30 years ago and began moving closer to the West. Poland has since joined NATO and the European Union, and has cultivated a close alliance with the United States.

Poland has also been making efforts to reduce its dependence on Russian gas and oil and has vocally opposed Nord Stream 2, a major Russian-German gas pipeline under construction that will transport Russian gas to Western Europe, bypassing Poland and Ukraine.