US Secretary of Transportation John Volpe, the mayor of Los Angeles and representatives and transportation specialists from over 18 countries came to France and participated in test rides, studied the system and reported on the Aérotrain. Bertin felt the technology was sufficiently realized for full implementation, and the French government signed a contract to implement full-scale service on the outskirts of Paris, between Cergy and La Défense. The Aérotrain nonetheless ran into increasing internal conflicts with its client SNCF, which had no research and development department of its own and strongly favored improving the existing rail system.