Why did Gustav Stresemann sign the Treaty of Berlin with the Soviet Union in 1926?

Gustav Stresemann signed the Treaty of Berlin with the Soviet Union on April 24, 1926, primarily to reassure the Soviets regarding Germany's international standing.1

Following the Locarno Pact, the Soviet Union viewed Germany’s diplomatic shift toward the Western powers with deep suspicion, fearing that Germany might join an anti-Soviet bloc. To alleviate these concerns and maintain a balance in his foreign policy, Stresemann entered into this new agreement, which confirmed and extended the friendly relations previously established by the Treaty of Rapallo. The treaty functioned as an agreement of mutual neutrality, allowing Stresemann to navigate Germany's central position in Europe by exploiting tensions between the Western powers and the Soviet Union. Unlike his Western-facing policies, this treaty received unanimous support from German political parties, including those on the right.12