The aim of this paper is the three dimensional reconstruction of urban areas using Very High Resolution (VHR) images. The proposed innovative approach for the three dimensional reconstruction is based on the joint exploitation of both amplitude and interferometric phase images of a multichannel SAR system. The information provided by the amplitude data is added to the 3D reconstruction chain, considering that in urban areas edges of amplitude image are likely also present in the interferometric phase one and conversely. Differently from other works present in literature, the proposed technique exploits the amplitude image, not only to improve the phase regularization, but also to improve the phase unwrapping step. The results will show the effectiveness of the method.