The V⁰ centre in magnesium oxide consists of two holes trapped by a magnesium vacancy. The hyperfine spectrum due to interactions between this S=1 spin system and two equivalent neighbouring ²⁵Mg axial nuclei has been observed and values for the isotropic and anisotropic hyperfine parameters and the nuclear quadrupole parameter are presented. This provides further verification of the ground-state model in which the two holes are localized on opposite sides of the magnesium vacancy. The existence of a 'negative' transferred contact interaction with the axial neighbour nuclei has been conclusively shown. Hyperfine lines from the equatorial magnesium neighbours are observed but not analysed in detail.