We present herein a method for the numerical coupling of one and two-dimensional Euler isentropic models through a thin interface. The basic approach is connected with recent works by E. Godlewski, A.Y. Leroux and P.A. Raviart. It requires introducing an interface model, and solving the associated Riemann problem at the interface between codes. Numerical results confirm both the stability and the fair accuracy of the admissible non-conservative approach, which is also compared with an admissible conservative approach and a reference two-dimensional solution. The extension to the full Euler set of equations is also briefly discussed.