Mae'r Bil yn darparu ar gyfer pwerau newydd i'r Ysgrifennydd Gwladol dros Fusnes a Strategaeth Ddiwydiannol “alw i mewn” materion cymhorthdal gan gyrff dyfarnu yng Nghymru ar gyfer adolygiad annibynnol gan yr awdurdod Cystadlaethau a Marchnadoedd.  Mae'r pwerau galw i mewn a ddefnyddir gan y Bil i rymuso'r Ysgrifennydd Gwladol dros Fusnes, Menter a Strategaeth Ddiwydiannol yn faen tramgwydd annerbyniol ar feysydd polisi datganoledig trwy roi pwerau i Lywodraeth y DU gyfyngu ar wneud penderfyniadau ar feysydd polisi datganoledig. Ni ddylai'r Bil Rheoli Cymorthdaliadau effeithio ar bwerau datganoledig Gweinidogion Cymru na bod yn arf i wrthdroi datganoli trwy ddrws y cefn.
The Bill provides for new powers for the Secretary of State for Business and Industrial Strategy to “call-in” subsidies issues by awarding bodies in Wales for independent review by the Competitions and Markets authority. The call-in powers with which the Bill empowers the Secretary of State for Business, Enterprise and Industrial Strategy serve as an unacceptable imposition upon areas of devolved policy by providing the UK Government with powers to constrain decision-making on areas of devolved policy. The Subsidy Control Bill should not impact upon the devolved powers of Welsh Ministers or act as a tool to reverse devolution through the back door.