[en] The two-nucleon problem is considered with the tensor forces assuming that nucleon-nucleon interaction is described by a boundary condition model. It is shown that in this case the off-shell t-matrix can be determined without the usual utilization of a certain limiting procedure for a special local potential. The expression for off-shell t-matrix and some relations important for the consideration of three-nucleon problem have been obtained with the help of boundary condition imposed upon the off-shell two-particle wave function only