Sanjabi and Allahyar Saleh led the Iran Party, a nationalist, progressive, leftist and anti-Soviet group, in the 1950s. The party became part of the National Front. Sanjabi was a loyal supporter of Mohammad Mossadegh and he later served as minister of education under Mossadegh in 1952. Mossadegh had led the movement to nationalize the British-controlled oil industry in Iran (which, after nationalization, became known as the National Iranian Oil Company) and after this was accomplished, he became engaged in a heated battle with the British (who had previously controlled the oil industry and wished to reassert control over it) and with the forces rallying around Mohammad Reza Shah (the king of Iran who was opposed to Mossadegh's policies vis-a-vis the British, as well as the prime minister's efforts at limiting the Shah's power and influence). After a CIA-MI6 coup d'état overthrew Mossadegh in August 1953 and reestablished the Shah on the throne, Sanjabi, along with other Mossadegh supporters, went into opposition against the Shah's regime. He was heavily involved in the formation of the Second National Front in 1960. The reconstituted National Front was to remain active for five years, but under increasingly worsening circumstances. Despite its moderate demands for electoral reforms and a Shah that would "reign and not rule", the Shah refused to tolerate the Front's activities. His powerful security forces, most notably the infamous SAVAK, silenced the likes of Sanjabi and other secular democrats. Due to this and a variety of other factors, it had dissolved by 1965. The Front was to remain dormant until the late 1970s. It was revived in late 1977 by Sanjabi as its leader.