On 25 March 1957, the Treaties of Rome (the Euratom Treaty and the EEC Treaty) were signed by the ECSC members and on 1 January 1958 they came into force. ... The Euratom treaty thus remains in force relatively unamended from its original signing.

Is UK still in Euratom?

The UK withdrew from the Euratom (European Atomic Energy Community) at the same time it left the EU on 31 December 2020, meaning new nuclear cooperation agreements needed to be put in place to permit the future supply of nuclear materials and equipment to the UK.

Why did UK leave Euratom?

Following the Brexit referendum, concern was raised that leaving Euratom had the potential to impact the UK's current nuclear operations, including fuel supply, medical radioisotope supply, waste management, cooperation with other nuclear states, and research, such as at the Culham Centre in Oxford.