There is a slight majority for Irish unification among people in Northern Ireland, according to a new poll.

The latest survey in Northern Ireland asked voters for their preference “in the event of a referendum on whether or not Northern Ireland should remain part of the United Kingdom”.

A total of 45% told the Lord Ashcroft poll they would vote to stay in the UK and 46% said they would choose to leave and join the Republic of Ireland.

This equates to a lead of 51% to 49% for unification if “don’t knows” and those who say they would not vote are excluded.

Some 59% of those surveyed who identified as having no religion said they would vote for Northern Ireland to leave the UK and join the Republic of Ireland tomorrow.

Lord Ashcroft, a former Conservative peer, has been a major independent public pollster of British political opinion since 2010.

He says that although the outcome in favour of Irish unification may be linked to Brexit anxiety, it should be not taken lightly by those in power.

“Such a result might also reflect the uncertainty and anxiety surrounding Brexit, the Irish border and its potential effect on life in the province, which could recede when the outcome is settled,” Lord Ashcroft said.

“Be that as it may, the result underlines what could be at stake in the quest for a workable Brexit solution on the island of Ireland.”

How people voted was divided by traditional political lines for the most part, however one in twenty self-declared unionists said they would opt for unification.

The over-65s was the only age group with a clear majority for staying in the union (55% to 34%) while 45-64s divided evenly, and a majority of those aged from 18-44 said they would vote for unification.

More than half of voters in Northern Ireland, including nearly one in five unionists, think Brexit strengthens the case for unification and nearly two-thirds think it makes unification “in the foreseeable future” more likely.

Nearly half of Northern Ireland voters say they feel less close to the rest of the UK than they did five years ago.

In terms of timescales, one in three unionists believe a border poll is likely to happen in the next ten years – as do nine in ten nationalists.

Although a majority of voters think that in a referendum tomorrow Northern Ireland would choose to remain part of the UK, when asked what the outcome would be in ten years’ time most believe the vote would be for unification, with only three in ten believing voters would choose the UK.

Brexit was a major theme in the poll, which highlighted a favourability to the backstop in order to prevent the UK leaving the EU without a deal, and the possibility of a re-emerging hard border.

Given the choice between leaving with a deal that includes the backstop or leaving with no-deal, six in ten Northern Ireland voters (including 96% of nationalists) said they would choose the backstop.

However, only one in five unionists say they are prepared to accept it and 77%  would rather leave with no-deal.

Nearly eight in ten unionists believe the backstop “separates Northern Ireland from the rest of the UK in unacceptable ways and the government should not agree to any deal that includes it”.

Lord Ashcroft’s last poll in Scotland similarly found a slight lead for leaving the UK and Scotland becoming an independent country.