The effect of pressure on the infrared spectra of H2O and D2O ice VII has been studied at room temperature and pressures between 2 and 15 GPa with a Fourier tranform infrared spectrometer and a diamond avil high-pressure cell. Two librational modes (&ngr;REu2 and &ngr;REu3), one bending mode (&ngr;2A2u1), and various overtone bands are well resolved. The stretching modes, &ngr;1 and &ngr;3, are poorly resolved due to overlap with diamond window absorption. Although &ngr;REu3 shows a very strong shift to higher frequency with pressure, &ngr;1 and &ngr;3 shift to lower frequencies and all other lines vary only slightly with pressure. Differences between the spectra of H2O and D2O are discussed.