Аннотация:We further develop the theory of the neutrino flavour oscillations accounting for the quantum decoherence effect engendered by the neutrino radiative decay in an external electromagnetic field. In particular, we have considered the most general form of the neutrino electromagnetic vertex and obtained in the explicit form the dissipative term in the neutrino master equation. It shown that the dissipative term depends on the neutrino radiative decay rates.