Corbyn has previously been a left-wing Eurosceptic. In the 1975 European Communities referendum, Corbyn opposed Britain's membership of the European Communities, the precursor of the European Union.[251] Corbyn also opposed the ratification of the Maastricht Treaty in 1993,[252] opposed the Lisbon Treaty in 2008,[253] and backed a proposed referendum on British withdrawal from the European Union in 2011.[254] Additionally, he accused the EU of acting "brutally" in the 2015 Greek crisis by allowing financiers to destroy its economy.[254][255]