Construction started before the choice of the main technology supplier, thus alignment design was set out to be compatible with all choices. Of the planned line, would be laid on bridges, and another in tunnels. However, plans were changed repeatedly, in particular those for city sections, following disputes with local governments, while construction work suffered from early quality problems. Planned operating speed was also reduced from to the maximum of high-speed trains on the market. Three competitors bid for the supply of the core system, which included the rolling stock, catenary and signalling: consortia led by GEC-Alsthom, today Alstom, one of the builders of France's TGV trains; Siemens, one of the builders of Germany's ICE trains; and Mitsubishi Heavy Industries, one of the builders of Japan's Shinkansen trains. In 1994, the alliance of GEC-Alsthom and its Korean subsidiary Eukorail were chosen as winner.