  We present a study of the M83 cluster population, covering the disc of the
galaxy between radii of 0.45 and 4.5 kpc. We aim to probe the properties of the
cluster population as a function of distance from the galactic centre. We
observe a net decline in cluster formation efficiency ($\Gamma$, i.e. the
amount of star formation happening in bound clusters) from about 26 % in the
inner region to 8 % in the outer part of the galaxy. The recovered $\Gamma$
values within different regions of M83 follow the same $\Gamma$ versus star
formation rate density relation observed for entire galaxies. We also probe the
initial cluster mass function (ICMF) as a function of galactocentric distance.
We observe a significant steepening of the ICMF in the outer regions (from
$-1.90\pm0.11$ to $-2.70\pm0.14$) and for the whole galactic cluster population
(slope of $-2.18\pm0.07$) of M83. We show that this change of slope reflects a
more fundamental change of the 'truncation mass' at the high-mass end of the
distribution. This can be modelled as a Schechter function of slope $-2$ with
an exponential cut-off mass ($M_{\rm c}$) that decreases significantly from the
inner to the outer regions (from 4.00 to $0.25\times 10^5$ M$_\odot$) while the
galactic $M_{\rm c}$ is $\approx1.60\times10^5$ M$_\odot$. The trends in \Gamma
and ICMF are consistent with the observed radial decrease of the $\Sigma({\rm
H}_2)$, hence in gas pressure. As gas pressure declines cluster formation
becomes less efficient. We conclude that the host galaxy environment appears to
regulate 1) the fraction of stars locked in clusters; 2) the upper mass limit
of the ICMF, consistently described by a near-universal slope $-2$ truncated at
the high-mass end.
