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 failures of retained EU law to operate effectively and other deficiencies (in particular under paragraphs (a), (b) and (c) of section 8(2) of that Act) arising from the withdrawal of the UK from the European Union.
Link: The Cash Controls (Amendment) (EU Exit) Regulations 2019
Source: Legislation .gov.uk