Er gwaethaf fy sylwadau, nid yw Llywodraeth y DU’n barod i drosglwyddo'r arian y mae ei angen i gwmpasu’r maes gwaith newydd hwn. Felly Llywodraeth Cymru fydd yn ysgwyddo’r gost o sefydlu a gweithredu’r trefniadau casglu a rheoli ar gyfer trethi datganoledig.   Rwyf wedi ymrwymo i ddarparu cymaint o wybodaeth gadarn am y gost â phosibl i Gynulliad Cenedlaethol Cymru yn ystod y broses graffu ar gyfer Bil Casglu a Rheoli Trethi (Cymru).  Ar hyn o bryd nid oes modd cynhyrchu amcangyfrif cadarn o gostau sefydlu neu weithrediadau.  Er hynny, ar sail y dystiolaeth  sydd ar gael, rwyf yn hyderus mai’r ffordd orau ymlaen a nodir yn y datganiad yw’r dewis mwyaf fforddiadwy.
Despite my representations, the UK Government is not prepared to transfer the funding needed to cover this new area of work.  So the additional cost of setting up and operating the collection and management arrangements for devolved taxes will fall to the Welsh Government.    I am committed to providing as much robust cost information as possible to the National Assembly for Wales during the scrutiny process for the Tax Collection and Management (Wales) Bill.  It is not possible at this stage to produce a robust estimate of the costs of set up or operations.  However, based on the evidence available, I am confident that the preferred way forward set out in this Statement is the most affordable option.