  Studying basic physical effects sustained in metamaterials characterized by
specific constitutive relation is a research topic with a long standing
tradition. Besides intellectual curiosity, it derives its importance from the
ability to predict observable phenomena that are, if found with an actual
metamaterial, a clear indication on its properties. Here, we consider a
nonlocal (strong spatial dispersion), lossy, and isotropic metamaterial and
study the impact of the nonlocality on the dispersion relation of surface
plasmon polaritons sustained at an interface between vacuum and such
metamaterial. For that, Fresnel coefficients are calculated and appropriate
surface plasmon polaritons existence conditions are being proposed. Predictions
regarding the experimentally observable reflection from a frustrated internal
reflection geometry are being made. A different behavior for TE and TM
polarization is observed. Our work unlocks novel opportunities to seek for
traces of the nonlocality in experiments made with nowadays metamaterials.
