 Gorbachev, 20 February 1989), which was the first official document for stopping nuclear tests.Despite the resistance of military–industrial complex of USSR, which supported continuation of nuclear tests, Boztayev consistently and persistently pursued policy for ending tests for two and a half years.On 29 August 1991 Semipaltinsk Nuclear test site was closed by the Decree of the President of Kazakhstan, Nursultan Nazarbaev.