“Nid yw’r gweinidogion yn Llundain wedi dangos unrhyw dystiolaeth inni eto o fanteision gadael y Farchnad Sengl a’r Undeb Tollau na sut y gallai cytundebau masnachu newydd fod cystal â chael mynediad i’r EU. Mewn gwirionedd, mae dogfennau gan Lywodraeth y DU, a ddaeth i’r amlwg yr wythnos hon, yn cytuno â’n dadansoddiad ni o’r economi ar ôl gadael yr UE.
“Ministers in London have yet to show us any evidence of the benefits of leaving the Single Market and the Customs Union or how new trade deals would replace the benefits of access to the EU. In fact, UK government documents that have come to light this week chime with our own analysis of a post-Brexit economy.