In the present paper a novel numerical method for solving the problem of two-phase flow with moving interfaces in both laminar and turbulent flow regimes is developed. The developed numerical method is based on the solution of the Reynolds-Averaged Navier Stokes equations in both phases separately with appropriate boundary conditions located at the interface separating the two fluids. The solution algorithm is performed on a regular and structured two-dimensional computational grid using the control volume approach. The complex shapes as well as the geometrical quantities of the interface are determined via the level set method. The numerical method is firstly validated against the prediction of the well known flow dynamics over a circular cylinder. Further, the numerical simulation of two colliding droplets in gas flow is numerically predicted showing the important dynamics associated with the different flow regimes considered. The remarkable capability of the developed numerical method in predicting turbulent two-phase flow dynamics enables us to predict further a wide range of two-phase flow industrial and engineering applications.