Petri nets are a powerful recognized formalism for the specification and verification of concurrent systems. To deal with systems whose time issues become fundamental, different time Petri nets extensions have been developed in the literature, each one being dependent on the application considered. For time critical systems their correctness depends not only on the logical one but also on the time constraints. In this paper, a supervisory control technique for P-time Petri nets is proposed. It relies on an actualization procedure based on a firing instant approach and the blocked markings identification.