Robin Niblett
Director, Chatham House

The debate about the UK's membership of the EU is likely to be a central theme of British politics in the coming year. In October of 2011, a motion in the House of Commons that called for a referendum on British membership of the EU gained the support of 81 Conservative MPs voting against the instructions of Party whips, the largest ever Conservative rebellion on Europe. Senior figures in the Conservative Party such as former Defence Secretary Liam Fox have openly endorsed calls for a referendum, while Prime Minister David Cameron has cautiously accepted that the case for a referendum on Europe could be made, although he does not believe the time is right.

The turmoil within the eurozone has served to intensify the debate about Britain's place within Europe. As the countries that use the single currency move toward some form of full fiscal union, the pressure among Conservative activists for the government to offer the British people a renewed democratic mandate on EU membership is likely to grow. At the same time, the continuing popularity of the UK Independence Party (UKIP), whose political platform is built around its opposition to Britain's membership of the EU, creates concerns among Conservatives that voters with strongly Eurosceptic views are being drawn away from the party.

The survey demonstrates growing public desire for a referendum and, within the context of a referendum, 49% of respondents said they would vote to leave the EU. However, the desire for a referendum should not imply be considered as a proxy measurement of Euroscepticism. Prominent pro-Europeans, including Peter Mandelson, a former European Commissioner as well as senior Labour minister, and Jon Cruddas, the head of Labour's current policy review, have suggested that a referendum is the best way to build a national consensus behind the UK's membership and future relations with the EU. Both have urged the Labour Party to support such a move. The survey also shows that amongst both Labour and Liberal Democrat voters, more would currently vote to remain in the EU than to leave (39%–37% for Labour; 44%–39% for Liberal Democrats), potentially making any referendum outcome more uncertain than the gross numbers might imply.

In addition, it is interesting to note that, in a question laying out a variety of options for further European integration, a plurality – 31% – opt for the idea of the UK remaining in a less integrated EU, against 26% who saw leaving the EU as their preferred option. This means that, when given a broader choice than in or out, only a quarter of the public said they would actually choose to leave.

Much would come down, therefore, to the timing and phrasing of any referendum. If it followed a successful negotiation about the position the UK would enjoy outside the eurozone but still inside the Single Market (after a repatriation of some competencies or with additional safeguards for the UK), then a vote to stay in may win the day. But, if a referendum were held as a matter of ideological principle or political expedience prior to a serious negotiation and reduced to a simple 'in/out' choice, then the survey indicates that a majority of the British public would choose to leave. There is also a strong possibility that other EU member states may not be minded to negotiate concessions to keep the UK inside the EU, leaving opponents of UK membership with a strong case to argue for a negative answer to a straight ‘in/out' choice.

It is worth noting, in this case, the strong view of opinion-formers concerning the UK's future membership of the EU. If a referendum were held, some 90% of opinion-formers intending to vote Labour, 75% voting Liberal Democrat and nearly 50% voting Conservative said they would choose to stay in the EU. Do they know something the public does not? And if so, could they make the case convincingly for Britain staying in the EU against the likely media onslaught for a British exit?