  The $pp\to pp\gamma$ bremsstrahlung cross section is calculated within the
method of coordinate space representation. It is shown that in the beam energy
range of 350--450~MeV a deep attractive NN-potential with forbidden states
(Moscow potential) and realistic meson exchange potentials (MEP) give rise to
the cross sections that differ essentially in shape: the cross sections nearly
coincide in the minima but differ by a factor of 5 approximately in the maxima.
Therefore, the $pp\to pp\gamma$ reaction at energies $\sim$350--450~Mev can be
used to study $NN$ interaction off-shell and to discriminate experimentally
between MEP and Moscow potential.
