  We show that propagation of ultrashort (few-cycle) pulses in nonlinear Drude
metamaterials with both electric and magnetic Kerr nonlinearities is described
by coupled generalized Short Pulse Equations. The resulting system of equations
generalizes to the case of metamaterials both the Short Pulse Equation and its
vector generalizations which describe the few-cycle pulses in dielectric
optical fibers beyond the slowly varying envelope approximation leading to the
nonlinear Schroedinger equation.
