<P> The Government of the United Kingdom has also to date held eleven major referendums within the constituent countries of England, Scotland, Wales and Northern Ireland on issues of devolution, sovereignty and independence; the first such referendum was the 1973 Northern Ireland border poll and, as of 2017, the most recent is the 2014 Scottish independence referendum . </P> <P> There have also been numerous referendums held by local authorities on issues such as temperance and directly elected mayors . </P> <P> Major referendums have been rare in the UK, and have only been held on major constitutional issues . Before Tony Blair's Labour government came to power in 1997, only four such referendums had been held . Historically referendums within the United Kingdom were opposed on the supposition that they violate the principle of parliamentary sovereignty . In May 1945 the then Prime Minister Winston Churchill suggested holding a referendum over the question of extending the life of his wartime Coalition until victory was won over Japan, be allowed to continue in office . However, Clement Attlee refused citing' I could not consent to the introduction into our national life of a device so alien to all our traditions as the referendum which has only too often been the instrument of Nazism and Fascism .' implying that referendums were a totally unknown and alien device to British politics . In March 1975 Margaret Thatcher also quoted Clement Attlee that referendums are "a device of dictators and demagogues" as Napoleon, Mussolini and Hitler had exploited their use in the past . </P> <P> There are two types of referendum that have been held by the UK Government, pre-legislative (held before proposed legislation is passed) and post-legislative (held after legislation is passed). To date the previous three UK - wide referendums in 1975, 2011 and 2016 were all post-legislative . Referendums are not legally binding, so legally the Government can ignore the results; for example, even if the result of a pre-legislative referendum were a majority of "No" for a proposed law, Parliament could pass it anyway, because parliament is sovereign . </P>

In what circumstances are referendums held in the uk
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