  In this paper we study the Ginzburg-Landau (GL) equation for Fermi liquid
superconductors with strong Landau interactions $F_0$ and $F_1$. We show that
Landau interactions renormalize two parameters entering the GL equation leading
to renormalization of superfluid density and separation of length and energy
scales for amplitude and phase fluctuations. The separation of energy/length
scales for amplitude and phase fluctuations in term leads to unconventional
(2D) KT transition and vortex liquid phase. Application of the GL equation to
describe underdoped high-$T_c$ cuprates is being discussed.
