In this paper we describe a waves-in-ice model which calculates ice breakage and the wave radiation stress (WRS) that is coupled to the new sea ice model neXtSIM, which is based on the Elasto-Brittle (EB) rheology. We highlight some numerical issues involved in the coupling, and investigate the impact of the WRS, and of modifying the EB to lower the stiffness of the ice in the area where the ice has broken up (the marginal ice zone, or MIZ). <br><br> In experiments in the absence of wind, we find that wind waves can produce noticeable movement in loose ice (concentration around 70 %) – up to 36 km, depending on the material parameters of the ice that are used, and the dynamical model used for the broken ice. Swell waves do not produce any movement, as they are attenuated too little to induce a very large WRS. <br><br> In the presence of wind, we find that the wind stress dominates the WRS, which while large near the ice edge, decays exponentially away from it. This is in contrast to the wind stress which is applied over a much larger ice area. In this case (when wind is present) the dynamical model for the MIZ has more impact than the WRS, although that effect too is relatively modest. When the stiffness in the MIZ is lowered due to ice breakage, we find that on-ice winds produce more compression in the MIZ than in the pack, while off-ice winds can cause the MIZ to be separated from the pack ice.