  We develop Ginzburg-Landau approach to the problem of superconducting pairing
with large momentum under screened Coulomb repulsion (eta_K-pairing).
Two-component order parameter arising in this scheme can be associated with
charge and orbital current degrees of freedom of the relative motion of
eta_K-pair corresponding to superconducting and orbital antiferromagnetic
ordered states, respectively. All basic features of the phase diagram of
cuprate superconductors result directly from the eta_K-pairing concept.
