The issue was rendered moot when in 1920 Russia's Red Army invaded Azerbaijan and Armenia, ending the independence of both, followed in February–March 1921 by Georgia. Turkey took the opportunity to wrest back lands in the east from Armenia, and Georgia occupied the Lori neutral zone with Armenian approval, so as to prevent it falling into Turkish hands. The USSR's border with Turkey was finalised in October 1921 via the Treaty of Kars, thus fixing the western limit of the Armenia–Georgia border. When the Soviets had established a degree of firm control in the area in early 1921 they sponsored a final border delimitation between Armenia and Georgia, splitting the Lori neutral zone in two (mostly in Armenia's favour) and fixing the border at its current location, an arrangement finalised on 6 November 1921. In 1922 all three states were incorporated into the Transcaucasian SFSR within the USSR, before being separated in 1936.