In the preceding Comment, Williams and Tallon do not agree with our interpretation of the thermal conductivity peak of ${\mathrm{YBa}}_{2}({\mathrm{Cu}}_{1\ensuremath{-}x}{\mathrm{Zn}}_{x}{)}_{3}{\mathrm{O}}_{7\mathrm{\ensuremath{-}}\mathrm{\ensuremath{\delta}}}$ compounds as a function of x and \ensuremath{\delta} in terms of a van Hove scenario of high-${T}_{c}$ superconductivity. Their main claim is that Zn doping does not lead to the variation of hole concentration in the ${\mathrm{CuO}}_{2}$ planes, but rather to pair-breaking effects, i.e., the strong scattering limit of the d-wave energy gap parameter. Williams and Tallon quote in their Comment various experimental data in order to support this latter interpretation. In this Reply, we argue that the van Hove scenario picture discussed in our commented paper seems consistent for oxygen- and zinc-doped ${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7\mathrm{\ensuremath{-}}\mathrm{\ensuremath{\delta}}}.$