Electromagnetic as well a strong interactions play a significant role in the elastic scattering of unpolarized charged hadrons. One can describe relatively easily separate actions of the two dynamics, but their combined action is still an open question, although several attempts at deriving a relative phase of the corresponding amplitudes have been made. A new formula for this relative phase within an eikonal model enabling a unified description of this scattering in the whole kinematically allowed region of momentum transfers is proposed. Its test for the elastic pp scattering at energy 53GeV and for pp scattering at energy of 541 GeV is given.