A method for inter-coding video is provided in which transmission bandwidth requirements associated with second motion vectors for bi-directional temporal prediction is reduced. In the method motion vector information for only one of the two motion vectors for bi-directional temporal prediction can be transmitted together with information on how to derive or construct the second motion vector. Thus, rather than sending express information regarding two motion vectors, express information related to only one motion vector along with information related to reconstruction/derivation of the second motion vector is transmitted, thus reducing bandwidth requirements and increasing coding efficiency.