Babrak Karmal always been highly critical of his Khalqist predecessors Nur Muhammad Taraki and Amin's ultra-left radicalism. Karmal was promoted to Chairman of the Revolutionary Council and Chairman of the Council of Ministers on 27 December 1979. He remained in office until 1981, when he was succeeded by Sultan Ali Keshtmand. Throughout his term, Karmal worked to establish a support base for the PDPA by introducing several reforms. Among these were the Fundamental Principles of the Democratic Republic of Afghanistan, introducing a general amnesty for those people imprisoned during Nur Mohammad Taraki's and Amin's rule. He also replaced the red Khalqist flag
1979 in Afghanistan one time estimated to number 140,000. Amin is overthrown and killed in a coup backed by Soviet troops. Viktor Karpukhin carries out the taking of the presidential palace, in which two Soviet soldiers are killed. Ex-deputy prime minister Karmal, who has been in exile in Czechoslovakia, is picked as Amin's successor. The Soviets have begun a massive military airlift into Kabul, and at least two motorized divisions have crossed the Soviet-Afghan border. Babrak Karmal, whose Parcham party spearheaded the coup against Daud but later lost power to the faction led by Taraki and Amin, is considered more pro-Soviet than Amin