Fears for the future of the Union move centre stage in Theresa May’s Brexit strategy, claims The Times

Meanwhile other senior Tories are warning that intrusive technology used to enforce a “smart border” could also undermine the support for the constitutional status quo among moderate nationalists. One idea for a British government smartphone app to track movement across the border is causing particular concern, amid fears that it would be unacceptable to republicans in the North.

Mrs May rejected claims by Mr Rees-Mogg that a referendum on the reunification would be easily won at a private meeting on Monday night. She argued that she was not prepared to take risks with the integrity of the Union. The intervention was seen by some Remain-supporting Tory MPs as an important argument in their favour, while angering hard Brexiteers who form part of the ERG.

The constitutional future of Northern Ireland is a live issue. Under the Belfast Agreement, the Northern Ireland secretary Karen Bradley is obliged to hold a poll “if at any time it appears likely to him (or her) that a majority of those voting would express a wish that Northern Ireland should cease to be part of the United Kingdom and form part of a united Ireland”.

Sinn Fein seized on today’s story in The Times to suggest a new referendum on Northern Ireland should be called immediately.

Michelle O’Neill, the Sinn Fein deputy leader, said: “If these reports are accurate, Theresa May is conceding that the Good Friday Agreement threshold for triggering a Unity poll has been met but that she isn’t prepared to allow the people of Ireland, North and South, to exercise their democratic right.

“That is an appalling display of contempt for the democratic rights of Irish citizens. It is also a fundamental breach of the Good Friday Agreement which clearly provides for a referendum. Theresa May has no right to deny democratic entitlements to the people of Ireland, North and South.”

This renewed constitutional uncertainty comes on the day the Scottish Parliament is preparing to vote to deny legislative consent on the EU withdrawal bill, the first time that Holyrood and Westminster have clashed in this way, raising the constitutional temperature.

1. Polling suggests opinion shifting marginally on a united Ireland shifting generally
In October 2017, 2,080 Northern Ireland voters were asked by pollster LucidTalk whether “Northern Ireland should remain a part of the United Kingdom or leave the United Kingdom and join the Republic of Ireland as one nation”. Some 55 per cent said Ireland should remain part of the UK and 34 per cent said it should leave and join the Republic, with 10 per cent undecided and one per cent declining to say.

The pollster adds: “This margin is less than previous polls. Noticeably there are a high number of undecided – but (they) would be voters in such a poll”.

2. A hard Brexit – involving ‘no deal’ – could shift opinion in Northern Ireland decisively
This is the finding which is causing concern amongst some senior Tory MPs.

In December, LucidTalk asked 2,079 Northern Irish voters how they would vote in a border poll “in the context of a hard Brexit’ and Northern Ireland leaving the EU with no deal on the border, the Good Friday Agreement or citizen’s rights. The question in the referendum would be “should Northern Ireland remain in the EU through joining the Republic of Ireland or leave the EU by staying in the UK.”

The pollster recorded 48 per cent saying they would remain in the EU by joining the Irish republic in a United Ireland and 45 per cent saying they would leave the EU by staying in the UK. Six per cent were undecided and one per cent would not vote.

3. The October ‘tracking’ poll should be taken more seriously than the December “no deal” poll
Anthony Wells, director of political polling at YouGov, gives the poll taken in October about leaving a clean bill of health. “The question about whether NI should stay and the results can be taken at face value as a prediction of how people would vote if there actually was a vote at that point.”

However he suggests that people should be cautious about relying on the “hard Brexit” poll. He said: “The bottom line is that this relies on a series of hypothetical questions. If you ask ‘how would you vote in a referendum under these particular set of circumstances’, firstly people aren’t very good at predicting their own behaviour and secondly this gives certain factors undue prominence. In a real border poll there all sorts of other factors taken into consideration – history, the economy, politics and so on – but this question is worded with Brexit at the forefront, ahead of all other considerations.”

LucidTalk also says the “hard border” question was commissioned by “Gue/ngl”, the European Parliament group which includes Sinn Fein.

4. The circumstances in which Theresa May’s customs decision could change the already-fluid dynamic in Northern Ireland
In cabinet, Philip Hammond, Greg Clark, Karen Bradley and David Gauke have pushed for a so-called “customs partnership”, a plan which would see the UK continue to collect customs dues on behalf of the EU after Brexit. So long as standards for British goods remain closely aligned with the EU after Brexit, they claim this removes the need for a border between NI and the Republic.

Brexiteers including Boris Johnson, Michael Gove and Liam Fox, want the so-called “maximum facilitation” option. This involves a “facilitation” agreement with the EU, which would see both sides waving certain goods through the border without checks so long as advanced technology is used to monitor the situation.

5. Why there are fears intrusive technological solutions could be a problem for moderate nationalist areas of Northern Ireland
David Davis is pushing for smart technologies to be deployed to avoid physical checks. These could include Automatic Number Plate Recognition via CCTV cameras and drones, all of which would be a magnet for gangs.

However, there are fears that more sophisticated techniques bring their own challenges. A European Parliament report suggested that one solution would be Smartphone apps: “Information for goods and passengers can be exchanged through smartphone apps. This can include the provision of minimum information when crossing a border and the receipt of information (e.g. a barcode) by drivers to facilitate passing the border.” Another suggestion is that business on both sides of the border open their computer systems to the British government so goods can be tracked. A Tory source said: “How can we expect moderate republicans to submit to a British government tracking app being installed on their phones? This is just unreal.”

6. There is still the possibility of a compromise on customs
If Mrs May cannot agree the “max fac” or “customs partnership” options within the next two weeks, she will need a fudge. The most likely is that she promises the “max fac” option – eventually – but delays leaving the customs union by 5 or 6 years. This would be unacceptable to some Brexiteers like Boris Johnson and Michael Gove and Mr Rees-Mogg but the prime minister might hope that arguments about the integrity of the union buy off enough of the rest.

7. The DUP want to leave the customs union – but it isn’t a red line
In a little noticed Conservative Home interview, Nigel Dodds, the DUP Westminster leader, said their only “absolute red line” was a border in the Irish Sea. The party does not believe that staying inside the customs union respects the referendum result. However, he adds: “We believe that the proposals put forward by the Prime Minister in the paper last August for either a customs partnership, whereby we would collect the revenues and then pay them back if the goods go to Europe, or the maximum facilitation streamlined approach, we believe in that, but we don’t believe in staying in the Customs Union.

“But at the end of the day, as long as Northern Ireland is in lockstep with the rest of the United Kingdom, for us that’s the fundamental point.”

8. What Brexiteers say publicly about these challenges
The Times reported last night that Mr Rees-Mogg, chair of the 60-strong ERG downplayed the risk of losing a referendum on a united Ireland. Writing in the Telegraph, Mr Rees-Mogg said he was not minded to adopt a more conciliatory position

“If we were to do so it would completely undermine the heart of why we voted to leave, rendering our almost-reclaimed sovereignty a myth,” he said. He repeated calls for Britain to walk away from the negotiations if the options May gave the European commission were rejected. “The UK will simply have to leave with no deal because the referendum result must be upheld,” he said. “Democracy is the backbone of established political societies, it fosters stability and fairness and cannot be treated so disdainfully.”

9. What Brexiteers say privately about Mrs May’s intervention and the government position
One ERG source said the prime minister’s position was “purposeless and inexplicable”, repeating the fears over a united Ireland is “unbelievably stupid” and that a border poll would be won by the union “comfortably”. They warn it veers “amazingly quickly to signing her death warrant”, adding “I really won’t be surprised by leadership chatter this weekend.”

10. What happens next
Theresa May has about two weeks left for her cabinet and party to come to an agreement that can pass Parliament. It remains to be seen whether she has set herself too many red lines.