These Regulations are made in exercise of the powers conferred by section 8(1) of the European Union (Withdrawal) Act 2018 (c.16) in order to address the failures of retained EU legislation to operate effectively and other deficiencies (in particular paragraphs (a), (d) and (g) of section 8(2)) arising from the withdrawal of the United Kingdom from the European Union.
Link: The Animal By-Products and Transmissible Spongiform Encephalopathies (Amendment) (Northern Ireland) (EU Exit) Regulations 2019
Source: Legislation .gov.uk