1991 Sino-Soviet Border Agreement - Agreement

Agreement

The agreement largely finalized the 4,200 km (2,600 mi) border between the Russian Federation and the People's Republic of China, except for a few disputed areas. The agreement states the intentions of both parties in resolving and demarcating the disputed border peacefully, identifies the various points of contention, and identifies the border as running through the center of the main channel of any river, based on the thalweg principle. The location of the main channel and the possession of the various islands would be decided in the course of the demarcation work. Various other articles stipulate military, usage, and traffic rights along the river borders. Two areas, Heixiazi and Abagaitu Islet, were excluded from the agreement, and their status would not be resolved until 2004. According to the estimates by Boris Tkachenko, a Russian historian, the treaty resulted in net territorial gain for China, which received about 720 km², including some seven hundred islands.

Because islands on the Argun, Amur, and Ussuri rivers often split the rivers into multiple streams, the location of the main stream (and thus the border) was often not immediately apparent. Obviously, each country would receive a greater number of islands if the recognized main channel was closer to the opposite bank. Thus, the demarcation work was often controversial and subject to local protests over disputed territories. The demarcation work continued nearly up until its 1997 deadline.