Light-front projections of the Bethe-Salpeter amplitude and the 4D electromagnetic current for an interacting two-fermion system

A recent approach for constructing an exact 3D reduction of the 4D matrix elements of the electromagnetic current for an interacting two-fermion system, is briefly reviewed. The properties of the obtained 3D current, like the fulfillment of the Ward-Takashi Identity and its Fock decomposition, will be illustrated in relation with future applications to few-nucleon systems.