between 1975-2016, from factions of the Conservative Party in the 1980s-2000s, no further referendums on the issue were held.

By the mid-2010s, the growing popularity of the UK Independence Party (UKIP), as well as pressure from Eurosceptics within his own party, persuaded the Conservative prime minister David Cameron to promise a referendum on British membership of the EU if his government was re-elected.