project also. The French prototypes were developed and produced by the Atelier de Construction d'Issy-les-Moulineaux, under the direction of General Joseph Molinié of the Direction des Études et Fabrications d'Armements (DEFA, the later Direction Technique des Armements Terrestres) and AMX head engineer Heissler, The first prototype was completed in September 1960 and tested from February 1961; the second, with an improved range finder and track was tested in July 1961. These first vehicles had a very rounded turret, in a deliberate imitation of the Soviet T-54, and Sofam petrol engines. Another seven, with an improved sleeker turret cast, were manufactured between 1961 and 1963. Work on the German prototypes was carried out by two teams, including Team A composed of Porsche, Maschinenbau Kiel, Luther & Jordan and Jung-Jungenthal . Team B was made up by Ruhrstahl, Rheinstahl-HANOMAG and Henschel. Wood mock-ups were completed in 1959, while the first two prototypes were finished by 1961 (completed by Team A). Development history De Gaulle decided that France, though formally remaining a member, would no longer participate in the NATO military organization. This caused a rift between France and West Germany, which then started to emphasize standardization with American equipment, especially in armament, and to follow the new NATO policy to use multifuel diesel engines. German defence minister Franz Josef Strauss began to oppose the common tank project. In July 1963, the defence committee of the German Bundesrat decided to procure a purely national tank. In response, the same month the French government decided likewise. Comparative trials were nevertheless held at Mailly-le-Camp, Meppen, Bourges and Satory between five French and five German prototypes between August and October 1963, under Italian, Dutch, Belgian and American supervision. The French type had received a separate national designation: AMX 30. The trials indicated that the German type, on 1 October also getting its own name Leopard, had a better mobility and acceleration. The French government decided that it could not procure a new tank until 1965, while the Germans refused to adopt the Franco-German tank gun, in lieu of the British Royal Ordnance L7, of which they had already ordered 1,500 in the autumn of 1962, their plan having failed for Rheinmetall to produce in Germany a common type of munition of sufficient quality. Suggestions to save the project by combining the French turret with the German chassis failed. As a result, the program was cancelled and