  We consider a disordered two-dimensional electronic system in the limit of
high magnetic field at the metal-insulator transition. Density of states close
to the Fermi level acquires a divergent correction to the lowest order in
electron-electron interaction and shows a new power-law dependence on the
energy, with the power given by the anomalous diffusion exponent $\eta$. This
should be observable in the tunneling experiment with double-well GaAs
heterostructure of the mobility $\propto 10^{4}V/s$ at temperatures of $\propto
10 mK$ and voltages of $\propto 1 \mu V$.
