Sometime before the end of 2017 – and probably later this year – the UK is to have a referendum on whether to remain in the European Union or not.  Given the importance of the issue, there has been an enormous amount of polling looking at the issue. It shows a close race – with one poll-of-polls currently standing at 51:49 to remain.

But what of party elites? This is an area where there had been much speculation, but little hard evidence. So, funded by the UK in a Changing Europe initiative, we commissioned Ipsos MORI’s Reputation Centreto conduct a survey of MPs, designed to tap into what those who sit on both sides of the Commons really think.

It showed that a large number of Conservative MPs were still to make up their minds on the referendum – something which they have in common with their grassroots party members. But it also revealed fundamental differences between the parties on the way they viewed the EU. Almost 90% of Labour MPs, for example, agreed with the claim that ‘the UK has greatly benefited from being a member of the EU’. The equivalent figure for Tories was just 25%. 

We asked MPs what the European Union meant to them personally. For Conservatives, it meant ‘bureaucracy’ (77%), ‘not enough control at external borders’ (64%), and ‘waste of money’ (46%). For Labour MPs it meant ‘freedom to travel, study and work anywhere in Europe’ (82%), ‘economic prosperity’ (74%), ‘a stronger say in the world’ (70%) and ‘peace’ (65%).  

We also asked which, if any, of a list of adjectives described their feelings about Britain's membership of the EU. Some 69% of Conservative MPs picked ‘uneasy’, although only (if that’s the right word) 25% chose ‘angry’.  Labour MPs went for ‘hopeful’ (64%), followed by ‘proud’ (42%), ‘happy’ (37%), and ‘confident’ (37%).

Some 69% of Labour respondents didn’t have a bad thing to say about the EU. Some 74% of Conservative respondents didn’t have a single good thing to say about it.

They may as well be talking about two completely different organisations.

What of the future? We asked MPs if they thought integration had gone too far or should go further. Not a single Conservative MP backed any further integration; 40% of Labour MPs did so. Confronted with an 11-point scale on this question, a full 64% of Conservative MPs selected the most Eurosceptic option available, compared to just 5% of their Labour counterparts.

There was just as big a difference when it came to two specific policies we tested – the restriction of EU citizens’ right to work in other member states and ensuring they could only claim welfare in their country of origin.  When it came to the latter, almost three quarters of Conservative MPs supported the proposal compared to under a third of Labour MPs.

It is common to talk about the extent to which the issue of Europe divides political parties, and especially the Conservatives. And, true, there were divisions in both the major Westminster parties. Just as there are a handful of Tory MPs who are proud of the EU, who think is had benefited the UK, and has contributed to peace in Europe, there are a few Labour MPs who oppose further integration, think the EU is a waste of money, and want out.

But any divisions within the parties pale compare to the divisions between them. The EU is now much more an inter-party split than an intra-party one.

On one question, however, there was less disagreement. Regardless of how they are going to vote, clear majorities of both Conservative and Labour MPs currently think that the referendum will result in Britain remaining part of the EU.

But what the survey showed was that while David Cameron may take many of his parliamentary colleagues, as well as the country, with him in the referendum, our research suggests that there is little that he or anyone else can do to truly reconcile them to the idea of Britain in Europe.