GOV.WALES uses cookies which are essential for the site to work. Non-essential cookies are also used to tailor and improve services. By continuing to use this site, you agree to our use of cookies.
Roedd y Ddeddf yn ofynnol i roi'r Cytundeb Ymadael ar waith er mwyn iddo gael effaith gyfreithiol ddomestig ac i alluogi Llywodraeth y DU i gadarnhau'r Cytundeb Ymadael.