In 1920 Russia's Red Army invaded Azerbaijan and Armenia, ending the independence of both, followed in February–March 1921 by Georgia. On 5 July 1921 Russia confirmed that the non-disputed sections of the Azeri-Georgian border would remain as they were, whilst transferring Zakatal to Azerbaijan, with this arrangement finalised by treaty on 15 November 1921. In 1922 all three states were incorporated into the Transcaucasian SFSR within the USSR, before being separated in 1936.