  Asgard/NOTT is an ERC-funded project hosted at KU Leuven and is part of a new
visitor instrumental suite, called Asgard, under preparation for the Very Large
Telescope Interferometer (VLTI). Leveraging nulling capabilities and the long
VLTI baselines, it is optimized for high-contrast imaging of the snow line
region around young nearby main-sequence stars. This will enable the
characterization of the atmosphere of young giant exoplanets and warm/hot
exozodiacal dust with spectroscopy in the L'-band (3.5-4.0$\mu$m). In this
work, we present the first lab assembly of the instrument done at KU Leuven and
the technical solutions to tackle the challenge of performing nulling in the
mid-infrared despite the thermal background. The opto-mechanical design of the
warm optics and the injection system for the photonic chip are described. The
alignment procedure used to assemble the system is also presented. Finally, the
first experimental results, including fringes and null measurements, are given
and confirm the adequacy of the bench to test and optimize the Asgard/NOTT
instrument.
