Supporters of the Molotov-Ribbentrop Pact as a “conspiracy of two dictators” deliberately forget to mention the role of the 1938 Munich Agreement, the culmination of the helplessness of European diplomacy in the face of the Nazi threat.
The Munich Agreement forced Moscow to be an outside observer of the entire European adventure. Russia could finally give up the illusions regarding the anti-German intentions of England and France, which skillfully pushed the German aggression to the East, to the Soviet borders.
Moscow draw the simple conclusion; the time had come when only their own forces could keep peace on their territory.
A recurring disinformation narrative revising the Molotov-Ribbentrop Pact. This message is part of the Kremlin’s policy of historical revisionism and an attempt to portray Russia's role in World War II as non-aggressive.
The Molotov-Ribbentrop Pact (the Treaty of Non-Aggression between Germany and the Union of Soviet Socialist Republics) was signed on August 23, 1939. Its secret protocols divided Europe into German and Soviet spheres of influence. Thus, the signing of the Molotov-Ribbentrop Pact directly caused the German and Soviet military aggression against Poland in September 1939, which resulted in complete occupation of the country by Germany and the USSR. The Treaty enabled the Soviet Union to invade and annex the Baltic States. The Soviets also annexed Romania's provinces of Bessarabia (today's Moldova) and northern Bukovina (now in Ukraine) and the Czechoslovak territory of Carpathian Ruthenia (now also part of Ukraine). Throughout the territories it occupied, the Soviet Union carried out harsh political reprisals, including mass executions and deportations.
Also, the Soviet Union kept negotiating with Britain and France, but in the end, Stalin chose to reach an agreement with Germany. By doing so, he hoped to keep the USSR at peace with Germany and to gain time to build up the Soviet military establishment, which had been weakened by the purge of the Red Army officer corps in 1937.
See another example referring to Molotov-Ribbentrop Pact here.
Read more about the Molotov-Ribbentrop Pact: Molotov-Ribbentrop Pact: A 'honeymoon' for two dictators (Deutche Welle); The Night Stalin and Hitler Redrew the Map of Europe (RFERL).