hierarchy of decision making into the PTP. The bilevel programming is motivated by the fact that many planning problems contain a hierarchical decision structure where each level has independent and often conflicting objective ([2]). Bilevel programming is the simplest case of such a situation where there are only two independent decision makers located at different levels of decision making. The one on the upper level is called the leader, and the one on the subordinate level is called the follower. Furthermore, the situation of perfect information is assumed, meaning that each player is familiar with the objective as well as the choices available to the other. Each player is entitled to one move only. The leader acts first. When making the decision, he must anticipate all possible responses of the follower. Given the decision of the leader, the follower reacts in a way that is personally optimal for him. Therefore, the sets of feasible choices available to each of the players are interdependent. Moreover, the leader's decision affects both the follower's objective and available decisions and vice versa.