On 20 March 1939, after years of rising tensions, Lithuania was handed an ultimatum by Nazi Germany demanding it relinquish the Klaipėda Region. Two days later, the Lithuanian government accepted the ultimatum. When Nazi Germany and Soviet Union concluded the Molotov–Ribbentrop Pact, Lithuania was initially assigned to the German sphere of influence but was later transferred to the Soviet sphere. At the outbreak of World War II, Lithuania declared neutrality.