  We have investigated the Hall resistance $R_H$ near the plateau-insulator
transition of a two-dimensional electron gas in the quantum critical regime.
High-field magnetotransport data taken on a low-mobility InGaAs/InP
heterostructure with the plateau-insulator transition at a critical field $B_c$
of 17.2 T show that the Hall resistance $R_H$ is quantized at $h/e^2$ near the
critical filling fraction ($\nu_c$ = 0.55) when $T \to 0$. By making use of
universal scaling functions extracted from the magnetotransport data we show
that $R_H$ in the insulating phase in the limit $T \to 0$ is quantized at
$h/e^2$ for all values of the scaling parameter $\Delta\nu /(T/T_0)^\kappa$
with $\Delta\nu = \nu - \nu_c$. However, as a function of $\Delta\nu $ (or
magnetic field) the Hall resistance diverges in the limit $T \to 0$ for all
values $\nu < \nu_c$.
