  We present the results of a $\lambda$20 cm VLA observation of the compact
Galactic center radio source Sgr A$^*$. The scatter-broadened image is
elongated in the East-West direction, with an axial ratio of 0.6$\pm$0.05 and a
position angle of 87$^0\pm$3$^0$. A similar shape and orientation has been
found previously at shorter wavelengths using VLBI and VLBA. Both the major and
minor axes follow the $\lambda^2$ law appropriate for scattering by turbulence
in the intervening medium. Assuming that the anisotropy is caused by a magnetic
field permeating the scattering medium, we argue that the scattering occurs
within extended HII regions lying in the central 100 pc of the Galaxy. The
magnetic field in this region must be poloidal, organized and is estimated to
have a strength of at least 30 to 100 $\mu$Gauss.
