  We consider the space-time metric generated by a global monopole in an
extension of General Relativity (GR) of the form
$f(\mathcal{R})=\mathcal{R}-\lambda \mathcal{R}^2$. The theory is formulated in
the metric-affine (or Palatini) formalism and exact analytical solutions are
obtained. For $\lambda<0$, one finds that the solution has the same
characteristics as the Schwarzschild black hole with a monopole charge in
Einstein's GR. For $\lambda>0$, instead, the metric is more closely related to
the Reissner-Nordstr\"{o}m metric with a monopole charge and, in addition, it
possesses a wormhole-like structure that allows for the geodesic completeness
of the space-time. Our solution recovers the expected limits when $\lambda=0$
and also at the asymptotic far limit. The angular deflection of light in this
spacetime in the weak field regime is also calculated.
