This article deals with the territorial claims of Armenia against Azerbaijan and the diplomatic struggle among related parties after the establishment of independent states in the South Caucasus. Azerbaijani and Armenian delegations at the Istanbul conference on Armenia's territorial claims, and at the same time, details of the negotiations between the diplomatic representatives of the two countries in Tbilisi have been illustrated according to the documents of the archives of Azerbaijan and Turkey and materials from the Istanbul press in 1918. (...) The scale of the territorial claims of Armenia and the arguments referenced by Armenians have been identified. Also, contrary arguments made by the Azerbaijani side against these allegations have been interpreted. Archival documents, notes, and statements of the parties presented on the problem were brought into scientific circulation for the first time. It was concluded that the total territory of Armenia, whose independence was declared on May 30, 1918, was only 9000 km2. This territory was also given to Armenia under a number of conditions. After the declaration of independence, Armenia made territorial claims against all states with which it has a territorial border. The total volume of Armenia's territorial claims is 43500 km2, of which 17600 km2 is directed against Turkey, 16500 km2 against Azerbaijan, and 9400 km2 against Georgia. Armenia referred to racial-national principles, Azerbaijan to ethnic-religious and geographical principles, and Georgia to historical principles to resolve disputed territorial-border issues between South Caucasus republics. The position and behavior of Armenia did not allow to resolve the disputed territorial and border issues between the South Caucasus republics. (shrink)