Channel Tunnel terms of the Concession, Eurotunnel was obliged to investigate a cross-Channel road tunnel. In December 1999 road and rail tunnel proposals were presented to the British and French governments, but it was stressed that there was not enough demand for a second tunnel. A three-way treaty between the United Kingdom, France and Belgium governs border controls, with the establishment of "control zones" wherein the officers of the other nation may exercise limited customs and law enforcement powers. For most purposes these are at either end of the tunnel, with the French border controls on the UK side of the tunnel
History of rail transport in France of the private railway operating companies began to face financial difficulties. In 1938 the socialist government fully nationalised the railway system and formed the "Société Nationale des Chemins de fer Francais" (SNCF). Regional authorities have begun to specify schedules since the mid of the 1970s with general conventions between the regions and the SNCF since the mid-1980s. From 1981 onwards, a newly constructed set of high-speed TGV ("Train à Grande Vitesse") lines linked France's most populated areas with the capital, starting with Paris-Lyon. In 1994, the Channel Tunnel opened, connecting France and Great Britain by rail under the English Channel.