The UK NARIC is the agency on behalf of the UK government (more specifically, Department of Education) which is responsible in comparing qualifications overseas to that in the UK, on their website they mentioned:
UK NARIC is the designated United Kingdom national agency for the recognition and comparison of international qualifications and skills. It performs this official function on behalf of the UK Government.
One of their service include issuing a statement of comparability, which in their words:
The UK NARIC Statement of Comparability is a document that can be used in support of your international qualifications.
It guides universities, colleges, employers and professional bodies on how your qualifications (including professional qualifications) relate to UK qualifications and certificates.
