A new analysis, aimed at improving the current ANTARES measurement of the atmospheric neu-
trino oscillation parameters, is presented in these proceedings. Two different track reconstruction
procedures are combined in order to increase the sensitivity. Furthermore, a novel method to
estimate the neutrino energy is applied. A complete 3-flavour description of the oscillation prob-
ability including matter effects in the Earth is used. By performing a two-dimensional fit of the
event rate as a function of reconstructed energy and zenith angle, expectations on the sensitivity to
the oscillation parameters are derived. Using the same analysis chain, a study on the ANTARES
sensitivity to sterile neutrinos is performed.