In a method of video decoding in a decoder, a merge candidate list of a current coding block is constructed for processing the current coding block with a triangular prediction mode (TPM). The merge candidate list can include merge candidates each having one or two motion vectors. Each motion vector can be associated with a first reference picture list or a second reference picture list. A first motion vector and a second motion vector are determined from the motion vectors of the merge candidates on the merge candidate list. The current block is processed with the TPM with the first and second motion vectors as two motion vector predictors (MVPs) of two triangular partitions of the current coding block.