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A new Hybrid Finite Volume discretization is proposed in this work for two-phase Darcy flow in Discrete Fracture Matrix (DFM) models accounting for nonlinear transmission conditions at matrix fracture (mf) interfaces. This type of model is more accurate than alternative hybrid-dimensional two-phase Darcy flow models based either on continuous phase pressures at the mf interfaces assuming fractures acting as drains, or based on the elimination of the mf interface phase pressures by harmonic transmissibility. On the other hand, keeping the pressure and saturation unknowns and the nonlinear flux continuity equations at the mf interfaces increases the difficulty to solve the nonlinear and linear systems due to the highly contrasted permeabilities, capillary pressures, and scales between the fractures and the matrix. In order to solve efficiently the nonlinear systems arising at each time step from the fully implicit time integration, a Newton solver with linear elimination and nonlinear update of the mf interface unknowns is derived. Numerical experiments show the efficiency of our approach on several 2D test cases including an anisotropic matrix permeability and a large fracture network.