Er bod y llinellau rheilffordd yng Nghymru yn rhyw 11 y cant o rwydwaith rheilffordd y DU, dim ond tua 1.5 y cant o'r arian a wariwyd gan Lywodraeth y DU ar wella'r rheilffyrdd sydd wedi dod i Gymru ers 2011.
Mr Skates pointed out that although the Wales route area has around 11 per cent of the railway track, since 2011 it has only benefited from around 1.5 per cent of the money spent by the UK Government on rail enhancements.