Russo–German agreement concerning their involvement in the Middle East.
From its inception, the German-dominated Berlin–Baghdad Railway project aroused the suspicion of the other European powers. On 6 through 9 August, 1911, Germany and Russia concluded an agreement at Potsdam, Germany, whereby Russia acquiesced to continued German involvement in the railway in return for a German affirmation of Russia's position in Persia (now Iran).
see also berlin–baghdad railway.
"Potsdam Convention." Encyclopedia of the Modern Middle East and North Africa. . Encyclopedia.com. (December 13, 2018). https://www.encyclopedia.com/humanities/encyclopedias-almanacs-transcripts-and-maps/potsdam-convention
"Potsdam Convention." Encyclopedia of the Modern Middle East and North Africa. . Retrieved December 13, 2018 from Encyclopedia.com: https://www.encyclopedia.com/humanities/encyclopedias-almanacs-transcripts-and-maps/potsdam-convention