Abstract: Developed in this paper is a novel deadlock control policy that can ensure concurrent execution of manufacturing assembly processes in flexible manufacturing systems (FMS) through a class of nets, called G-system that is a large class of discrete event systems. A relevant property of the system behavior is to be non-blocking, i.e., from any reachable state, a desirable state can be always reached under supervision. First, a maximal deadly siphon can be obtained by using the mixed integer programming technique, and a monitor is added to a minimal siphon that needs to be controlled, which is derived from the maximal deadly siphon in order to ensure the controllability of all siphons of Petri nets. Compared with the existing policies, the advantage of the proposed approach is that complete siphon enumeration is avoided and a much smaller number of monitors are added, which result in obtaining a simple supervisor with suboptimal permissive behavior.