These Regulations are made in exercise of the powers conferred by section 8 of the European Union (Withdrawal) Act 2018 in order to address failures of retained EU law to operate effectively and other deficiencies arising from the withdrawal of the United Kingdom from the European Union.
Link: The Greenhouse Gas Emissions Trading Scheme (Amendment) (EU Exit) (No. 2) Regulations 2019
Source: Legislation .gov.uk
