 During the period between the war and the perestroika in the late 1980s , Soviet historiography leaned solely on Vyacheslav Molotov 's speeches on the Winter War . In his radio speech of 29 November 1939 , Molotov argued that the Soviet Union had tried to negotiate guarantees of security for Leningrad for two months . However , the Finns had taken a hostile stance to " please foreign imperialists " . Finland had undertaken military provocation , and the Soviet Union could no longer hold to non @-@ aggression pacts . According to Molotov , the Soviet Union did not want to occupy or annex Finland ; the goal was purely to secure Leningrad . 
