Mae Rhaglen Lywodraethu Llywodraeth Cymru, a’r Cytundeb Cydweithio rhwng Llywodraeth Cymru a Phlaid Cymru, ill dau’n cynnwys ymrwymiadau i gyflwyno ardollau.
The Welsh Government’s Programme for Government, and the Cooperation Agreement between the Welsh Government and Plaid Cymru, both contain commitments to introduce levies.