How did USSR react to the rearming of West Germany?

German–Soviet Union relations date to the aftermath of the First World War. The Treaty of Brest-Litovsk, dictated by Germany ended hostilities between Russia and Germany; it was signed on March 3, 1918.[1] A few months later, the German ambassador to Moscow, Wilhelm von Mirbach, was shot dead by Russian Left Socialist-Revolutionaries in an attempt to incite a new war between Russia and Germany. The entire Soviet embassy under Adolph Joffe was deported from Germany on November 6, 1918, for their active support of the German Revolution. Karl Radek also illegally supported communist subversive activities in Weimar Germany in 1919.