  We consider a system of fermions with mass m and model repulsive interaction
U(q) = g/\sqrt{q^2 + q_0^2}, where q is the momentum transfer, q_0 the
screening constant, and g > 0 the coupling constant. It is shown that at g >
g_cr > 3\pi^2/m the system ground state is changed from fully occupied Fermi
sphere to multiconnected Fermi sphere (MFS), consisting in N fully occupied
spherical layers (icebergs) separated by empty spacers. An effective
description is developed for such states at N >> 1, showing their tendency at N
\to \infty to the Fermi condensate (FC) state known for the model U(q) = g/q
[Khodel, Shaginyan, JETP Lett., 51, 553, 1990]. At finite temperatures, a
crossover is predicted from the Fermi liquid behavior of MFS with effective
mass m^* \sim m N/ln(N) to non-Fermi-liquid behavior with m^* \propto 1/T at T
> T^* \sim T_F ln(N)/N.
