This contribution proposes a modified version of the Iterative Dynamic Programming (IDP) method. Two main differences to the original method are introduced. The new algorithm deals with discrete-time input-output models compared to continuous-time state-space models described by a set of ODE/DAE used in the original method. The main purpose of these modifications is to reduce computational load of the original method, estimate the process models more easily, and to enable its use on-line in receding horizon predictive control framework.