Mae'r Bil yn destun pryder mawr gan fod Llywodraeth y DU wedi dewis cyflwyno deddfwriaeth a allai, pe bai’n dod i rym, arwain at fethu â chyflawni'r rhwymedigaethau rhyngwladol yr ymrwymodd y Llywodraeth iddynt o’i gwirfodd pan gytunodd ar Brotocol Gogledd Iwerddon, fel rhan o'r Cytundeb Ymadael â'r Undeb Ewropeaidd. Yn wir, yn ei geiriau ei hun, mae Llywodraeth y DU wedi penderfynu: “to introduce legislative measures which, on entry into force, envisage the non-performance of certain obligations”. Mae Llywodraeth y DU yn ceisio cyfiawnhau hyn ar sail yr athrawiaeth “rheidrwydd” o dan gyfraith ryngwladol. Mae sylwebyddion cyfreithiol arbenigol annibynnol, gan gynnwys cyn-Gyfreithiwr y Trysorlys, Syr Jonathan Jones CF, wedi beirniadu hygrededd y dull hwn ac wedi mynegi pryderon ynghylch y pwerau Harri’r Wythfed newydd a geisir yn y Bil fel y’i drafftiwyd ar hyn o bryd.
The Bill is a matter of grave concern as the UK Government has chosen to introduce legislation that could, if enacted, lead to a failure to fulfil the international obligations it freely entered into when it agreed the Northern Ireland Protocol, as part of the Withdrawal Agreement with the EU. Indeed, in its own words, the UK Government has; “decided to introduce legislative measures which, on entry into force, envisage the non-performance of certain obligations”. The UK Government seeks to justify this on the basis of the international law doctrine of “necessity”.  Independent expert legal commentators, including the UK Government’sformer treasury solicitor,Sir Jonathan Jones QC have criticised the credibility of this approach and raised concerns about new Henry VIII style powers sought in the Bill as currently drafted.