  We suggest one of the possible ways to compensate the large negative
quantum-topological QCD contribution to the vacuum energy density of the
Universe by means of a positive constant contribution from a cosmological
Yang-Mills field. An important role of the exact particular solution for the
Yang-Mills field corresponding to the finite-time instantons is discussed. An
interesting connection of the compensation mechanism to the color confinement
in the framework of instanton models has been pointed out. Besides the
$\Lambda_{\rm QCD}$ scale, this proposal relies on one yet free dimensionless
normalisation constant which cannot be fixed by the perturbative QCD theory,
and thus should be fine-tuned for the exact compensation to hold.
