The Regulations and accompanying Explanatory Memorandum, setting out the detail of the provenance, purpose, and effect of the 2025 Regulations are available here (external link).
Rheoliadau Deddf Pleidiau Gwleidyddol, Etholiadau a Refferenda 2000 (Eithriadau ac Amrywio Terfynau Gwariant Ymgyrch) (Cymru) 2025: asesiad effaith integredig