<P> The Labour Party is a centre - left political party in the United Kingdom . It has been described as a broad church, bringing together an alliance of social - democratic, democratic - socialist and trade - unionist outlooks . The party's platform emphasises greater state intervention, social justice and strengthening workers' rights . Labour is a full member of the Party of European Socialists and Progressive Alliance, and holds observer status in the Socialist International . As of 2017, the party is considered the "largest party in Western Europe" in terms of party membership, with more than half - a-million members . </P> <P> The Labour Party was founded in 1900, having grown out of the trade union movement and socialist parties of the nineteenth century . It overtook the Liberal Party to become the main opposition to the Conservative Party in the early 1920s, forming minority governments under Ramsay MacDonald in 1924 and from 1929 to 1931 . Labour later served in the wartime coalition from 1940 to 1945, after which it formed a majority government under Clement Attlee until 1951 . Labour was next in government from 1964 to 1970 under Harold Wilson, and from 1974 to 1979, first under Wilson and then under James Callaghan . </P> <P> The Labour Party was most recently in government from 1997 to 2010 under Tony Blair and Gordon Brown, during the "New Labour" era, first elected with a landslide majority of 179, reduced to 66 in the 2005 election . Since leaving government the party has been led by Ed Miliband from 2010 and Jeremy Corbyn from 2015 . </P> <P> Labour is currently the Official Opposition in the Parliament of the United Kingdom, having won the second - largest number of seats in the 2017 general election . The Labour Party is currently the largest party in the Welsh Assembly, forming the main party in the current Welsh government . The party is also the third largest in the Scottish Parliament and sends the second most MEPs from the United Kingdom to the European Parliament, sitting in the Socialists and Democrats Group . Whilst the party organises in Northern Ireland, it does not contest elections there, instead supporting the Social Democratic and Labour Party . </P>

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