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 with a more traditional one. These policies failed to increase the PDPA's legitimacy in the eyes of the Afghan people and the mujahideen rebels. Karmal had always been highly critical of his Khalqist predecessors Nur Muhammad Taraki and Amin's ultra-left radicalism.