1939 German ultimatum to Lithuania was an oral ultimatum presented to Juozas Urbšys, Foreign Minister of Lithuania, by Joachim von Ribbentrop, Foreign Minister of Nazi Germany, on 20 March 1939. The Germans demanded that Lithuania give up the Klaipėda Region, which had been detached from Germany after World War I, or the Wehrmacht would invade Lithuania. After years of rising tension between Lithuania and Germany, increasing pro-Nazi propaganda in the region, and continued German expansion, the demand was expected. The ultimatum was issued just five days after the Nazi occupation of Czechoslovakia. The four signatories of the 1924 Klaipėda Convention, which had guaranteed the protection of the status quo in the region, did not offer any material assistance. The United Kingdom and France followed a policy of appeasement, while Italy and Japan openly supported Germany. Lithuania was forced to accept the ultimatum on 22 March. For Germany it was the last territorial acquisition before World War II; for Lithuania it was a major downturn in its economy and morale; for Europe it was a further escalation in pre-war tensions.