A new time-sequential approach for motion layer extraction is presented. We assume that the scene can be described by a set of layers associated to affine motion models. In one or more key frames, the segmentation is obtained using a semi-automatic method. At a subsequent instant, the first step of the proposed algorithm is the prediction of the segmentation from one image to the next one, using motion models estimated for each layer. The second step is the refinement of the predicted motion boundaries by graph cut. Only the appearing areas and a strip around the predicted boundaries are questioned. A new rigidity constraint improves the temporal consistency of foreground rigid objects. Experimental results show that our sequential approach is at least as effective as more complex simultaneous approaches while being less computationally demanding.