Mewn llythyr at Brif Weinidog y DU, mae Carwyn Jones a Nicola Sturgeon yn cydnabod bod cyfrifoldeb ar bob un ohonynt i gydweithio ar draws y Deyrnas Unedig i baratoi ar gyfer Brexit.
In a letter to the Prime Minister, both First Ministers acknowledge their shared responsibility to work together across the UK to prepare for Brexit.