O ran ariannu Metro'r De, mae'r Ysgrifennydd Gwladol dros Drafnidiaeth wedi cadarnhau eto ei ymrwymiad i dalu £125m (prisiau 2014) tuag at y gost.  Caiff hwnnw ei dynnu i lawr yn unol â gwariant. Mae'r cytundeb yn cynnwys mecanwaith hefyd ar gyfer ailgyfrif yr addasiad yn sgil trosglwyddo seilwaith Leiniau'r Cymoedd.
In terms of funding the South Wales Metro, the Secretary of State for Transport has reconfirmed his commitment to pay £125m (2014 prices) towards the cost, which we will draw down in line with expenditure. The agreement also includes a mechanism for calculating the adjustment following the transfer of the Valley Lines railway infrastructure.