Initial plans for the metro system were laid in late 1960s but could not be executed until 1982 due to socio-political issues such as the Iranian Revolution and the Iran-Iraq war. In 1970 the Plan and Budget Organization and the Municipality of Tehran announced an international tender for construction of a metro in Tehran. The French company SOFRETU, affiliated with the state-owned Paris transportation authority RATP, won the tender and in the same year began to conduct preliminary studies on the project. In 1974 a final report with a so-called "street-metro" proposal was tendered. The street-metro system recommended a road network with a loop express way in the central area and two highways for new urban areas and an 8-line metro network which were complemented by bus network and taxi services. Geological surveys commenced in 1976. In 1978 construction on the line was started in northern Tehran by the French company, however this development was short-lived with the advent of the Iranian Revolution and Iran–Iraq War in 1979 and 1980 respectively. SOFRETU ceased operations in Iran in December 1980. On March 3, 1982, the Iranian Cabinet ministers formally announced the stop of Tehran Metro operations by the French company.