Starting from a three-dimensional reduction of the Bethe-Salpeter equation, a meson exchange pi N model is constructed. The resulting pi N potential includes the direct and exchange nucleon terms, sigma and rho exchanges terms, and direct and exchange Delta terms. Reasonable fits to the pi N low-energy phase shifts are obtained. The constructed meson exchange potential is then used to evaluate rescattering effects in the dipole amplitude E₀₊ of pi ⁰ photoproduction from protons near threshold. The results are close to the most recent Mainz data.