  We consider two rubidium atoms, prepared in the same S or P Rydberg states
near an optical nanofibre. We determine the van der Waals interaction between
them and identify novel features, including the reshaping of the interaction
anisotropy and the formation of an interaction potential well near the
nanofibre for P states. We attribute these phenomena to the breaking of the
rotation symmetry around the interatomic axis due to the presence of the fibre.
Our work constitutes an important step in the assessment of Rydberg
atom-nanofibre quantum interfaces and devices.
