Exact loop-variables formulation of pure gauge lattice QCD_3 is derived from
the Wilson version of the model. The observation is made that the resulting
model is two-dimensional. This significant feature is shown to be a unique
property of the gauge field. The model is defined on the infinite genus surface
which covers regularly the original three-dimensional lattice. Similar
transformation applied to the principal chiral field model in two and three
dimensions for comparison with QCD.Comment: 6 pages, LaTeX (revision: references added