The parametric interaction of a fast wave pump field in the ion-cyclotron range of frequencies (ICRF) with the eta i-mode is considered. Using a two-fluid theory, the nonlinear dispersion relation of the eta i-mode in the presence of ICRF is derived. The condition for stabilization and destabilization of the eta i-mode is deduced. It is found that close to resonance, ICRF can have a strong effect on the eta i-mode.