Generalized Quantum Inverse Scattering

A generalization of the quantum inverse scattering method is proposed replacing the quantum group $RLL$ commutation relations of Lax operators by reflection equation type $RLRL$ commutation relations. Under some natural assumptions the most general algebra of this type allowing to construct the neccessary integrals of motion is found. It serves to describe Lax operators with completely non-ultralocal commutation relations. An example of this new formalism is an integrable model on monodromies of flat connections on a Riemann surface which is related to the XXZ quantum spin chain.