  We have studied neutron response of PARIS phoswich [LaBr$_3$(Ce)-NaI(Tl)]
detector which is being developed for measuring the high energy (E$_{\gamma}$ =
5 - 30 MeV) $\gamma$ rays emitted from the decay of highly collective states in
atomic nuclei. The relative neutron detection efficiency of LaBr$_3$(Ce) and
NaI(Tl) crystal of the phoswich detector has been measured using the
time-of-flight (TOF) and pulse shape discrimination (PSD) technique in the
energy range of E$_n$ = 1 - 9 MeV and compared with the GEANT4 based
simulations. It has been found that for E$_n$ $>$ 3 MeV, $\sim$ 95 \% of
neutrons have the primary interaction in the LaBr$_3$(Ce) crystal, indicating
that a clear n-$\gamma$ separation can be achieved even at $\sim$15 cm flight
path.
