 French officers and civilian officials were however forewarned of an attack through troop movements, and some garrisons were put on alert.The Japanese envoy in Saigon Ambassador Shunichi Matsumoto declared to Decoux that since an Allied landing in Indochina was inevitable, Tokyo command wished to put into place a "common defence" of Indochina.Decoux however resisted stating that this would be a catalyst for an Allied invasion but suggested that Japanese control would be accepted if they actually invaded.