  The branching ratio of the tau lepton to a neutral K meson is measured from a
sample of approximately 200,000 tau decays recorded by the OPAL detector at
centre-of-mass energies near the Z0 resonance. The measurement is based on two
samples which identify one-prong tau decays with KL and KS mesons. The combined
branching ratios are measured to be B(tau- -->pi- K0bar nutau) =
(9.33+-0.68+-0.49)x10^-3 B(tau- -->pi- K0bar [>=1pi0] nutau) =
(3.24+-0.74+-0.66)x10^-3 B(tau- -->K- K0bar [>=0pi0] nutau) =
(3.30+-0.55+-0.39)x10^-3 where the first error is statistical and the second
systematic.
