The M4 Motorway (Junction 23a (Magor), Monmouthshire to Junction 34 (Miskin), Rhondda Cynon Taf) & The A48(M) Motorway (Junction 29 (Castleton), Newport to Junction 29A (St Mellons), Cardiff) (Temporary Prohibition of Vehicles) Order 2018 / Gorchymyn Traffordd yr M4 (Cyffordd 23a (Magwyr), Sir Fynwy i Gyffordd 34 (Meisgyn), Rhondda Cynon Taf) a Thraffordd yr A48(M) (Cyffordd 29 (Cas-bach), Casnewydd i Gyffordd 29A (Llaneirwg), Caerdydd) (Gwahardd Cerbydau Dros Dro) 2018