  Recently, the {\it spacelike} part of the $SU(2)$ Yang--Mills equations has
been identified with geometrical objects of a three--dimensional space of
constant Riemann--Cartan curvature. We give a concise derivation of this
Ashtekar type (``inverse Kaluza--Klein") {\it mapping} by employing a
$(3+1)$--decomposition of {\it Clifford algebra}--valued torsion and curvature
two--forms. In the subcase of a mapping to purely axial 3D torsion, the
corresponding Lagrangian consists of the translational and Lorentz {\it
Chern--Simons term} plus cosmological term and is therefore of purely
topological origin.
