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It was signed by the Armenian Foreign Minister Alexander Khatisyan in the early hours of 3 December 1920. However, the previous day, the Armenian government in Yerevan had resigned and transferred power to a Soviet government, backed by Soviet Russia and so Khatisyan was no longer acting on behalf of the government of Armenia, and the treaty was technically invalid.
The terms of the treaty was prepared by the Turks, with the Armenians having no input. It required Armenia to cede to Turkey its entire province of Kars together with the Surmalu district of Yerevan province. A large part of the south of Yerevan province was also to be ceded to Azerbaijan.
The second item on the treaty acknowledged the border between the two countries. The Treaty of Alexandropol changed the boundary of the First Republic of Armenia to the Ardahan-Kars borderline and ceded over half of First Republic of Armenia to the Grand National Assembly of Turkey. The tenth item in the agreement stated that Armenia renounced the Treaty of Sèvres.
The Treaty of Alexandropol was to be ratified by the Armenian Parliament within a month. In the agreement signed by the resigning Armenian government and Soviet Russia's representatives in Yerevan, Russia recognised the boundaries of Armenia as they had been before the Turkish invasion. It was ratified as the Treaty of Kars, signed by the Grand National Assembly of Turkey and, at Soviet Russia's insistence, the three now-Soviet republics of Armenia, Georgia, and Azerbaijan.
Richard G. Hovannisian, The Contest for Kars (1914–1921), p. 316, Kars and Ani, Mazda Publishers 2011 (in Armenian).
Exact line is stated in Turkish as: "Türkiye ile Ermenistan arasındaki sınır, aşağı Karasu'nun döküldüğü yerden başlayarak Aras Irmağı Kekaç kuzeyine dek Arpaçayı, müteakiben Karahan Deresi, Tignis batısı, Büyük Kimli doğusu, Kızıltaş, Büyük Akbaba Dağı çizgisinden oluşur."