  New observations using narrow band imaging, long-slit spectroscopy and MERLIN
observations of the nuclear region of the Seyfert galaxy NGC~4051 have been
made. An edge brightened, triangular region of ionized gas extending 420 pc
from the centre of the galaxy has been detected. Long-slit spectra of this
ionised gas, taken at 1.5\arcsec\ from the core, show the \oiii\ emission line
to consist of two velocity components, both blue-shifted from the systemic
radial velocity, with velocity widths of 140\kms\ and separated by 120\kms.
This region is co-spatial with weak extended radio emission and is suggestive
of a centrally driven outflow. The \oiii\ line spectrum and image of this
region have been modelled as an outflowing conical structure at 50\degr\ to the
line of sight with a half opening angle of 23\degr .
  In addition to the extended structure, high resolution MERLIN observations of
the 18-cm nuclear radio emission reveal a compact (1\arcsec) radio triple
source in PA 73$^{\circ}$. This source is coincident with the HST-imaged
emission line structure. These high resolution observations are consistent with
a more compact origin of activity (i.e. a Seyfert nucleus) than a starburst
region.
