Almost half of British voters want to introduce passport checks between the UK and Ireland after Brexit, according to a major new opinion survey.

The report by NatCen Social Research found that 45 per cent backed passport checks on visitors from Ireland, with 29 per cent opposed and 25 per cent with no opinion.

Some 57 per cent of those who voted to leave the EU in June’s referendum back the proposal, compared to just 33 per cent of those who voted to remain.

The survey found that a big majority of voters want Britain to continue to have full access to the European single market but they favour strict controls on EU immigration by a similarly large margin.

Support for elements of a “soft” Brexit, such as access to the single market, is strong among Leave voters as well as among those who opposed Brexit. But voters on both sides of the referendum also want to curb immigration, to prevent EU citizens from using the National Health Service and to bring back customs checks on people and goods arriving from the EU.

Controlling immigration

“Irrespective of how they voted, voters in Britain do not feel that the UK’s exit from the EU should necessarily be a choice between a ‘hard’ or a ‘soft’ withdrawal. Rather, many back options on both menus.

“Consequently, the kind of deal that is most likely to prove electorally popular is one that maintains free trade but permits at least some limits on EU migration,” he said.

“That, of course, is the deal that many in the EU insist will not be possible. In those circumstances, the UK government will be faced with a tough choice. But given that most Leave voters – and, indeed, a majority of Conservative voters – prioritise limits on immigration over keeping free trade, perhaps we should not be surprised if that would be the choice that, if necessary, it will be inclined to make.”

MPs on the Northern Ireland Affairs Committee heard on Wednesday that, although the EU treaty protection of the Common Travel Area would survive Brexit, a customs border is likely.

Michael Dougan, a professor of European law at the University of Liverpool, told the committee that protocol 20 of the Lisbon Treaty, which protects the Common Travel Area, would not fall simply because Britain leaves the EU. He pointed out that two other treaty protocols guarantee Ireland’s right to opt out of parts of the EU’s immigration and open borders system.

Prof Dougan said, however, that if the UK leaves the EU customs union, there will be have to a customs border on the island of Ireland.

“The objective is to minimise the amount of disruption, to co-operate as closely and constructively as possible so as to keep trade flowing and minimise the disruption to people’s everyday lives. That’s the objective, but it will be there. There will be a customs border,” he said.