  If {\omega} is a closed G-invariant 2-form and {\mu} a moment map, then we
obtain necessary and sufficient conditions for equivariant pre-quantizability
that can be computed in terms of the moment map {\mu}. We also compute the
obstructions to lift the action of G to a pre-quantization bundle of {\omega}.
Our results are valid for any compact and connected Lie group G.
