Jean-Claude Juncker has voiced his concerns that the Stormont veto in Boris Johnson’s plans for the Irish border could see arrangements designed to keep the peace collapse as early as the end of 2020.

During a phone call with the prime minister, the European commission president highlighted the risk that the UK’s plans could unravel within 15 months, and set the communities in Northern Ireland against each other.

As part of its proposal to replace the Irish backstop, the British government suggests that Northern Ireland would leave the EU’s customs territory along with the rest of the UK but stay in regulatory alignment to avoid checks directly on the border.

The Northern Ireland assembly would need to give its consent to that special relationship with the EU’s single market in a vote by the end December 2020 when the standstill transition period ends. Stormont would have a vote every four years to confirm the decision.

If Stormont voted in 2020 against Northern Ireland staying in the EU’s single market for goods, the default position would be an effective no-deal situation with both Brussels and London under a legal requirement to restore a hard border.

Play Video 3:08 I love Europe, but … Boris Johnson announces his Brexit plan – video

Johnson’s plans make allowance for a year’s unravelling period during which both sides would try to rescue the situation but there are major concerns about the impact on relations in Northern Ireland in such circumstances.

In his 20-minute phone call with Johnson, Juncker pointed to the dangers in the prime minister’s approach citing the “problematic points that will need further work in the coming days, notably with regards to the governance of the backstop”, according to a commission statement. “The delicate balance struck by the Good Friday agreement must be preserved.”

Juncker also pointed out the continued problems with the UK’s plan for Northern Ireland to leave the EU’s customs territory, which would involve checks and controls to be reimposed on the island of Ireland.

Quick guide Why is the Irish border a stumbling block for Brexit? Show Hide Counties and customs Inside the EU, both Ireland and Northern Ireland are part of the single market and customs union so share the same regulations and standards, allowing a soft or invisible border between the two.

Britain’s exit from the EU – taking Northern Ireland with it – risks a return to a hard or policed border. The only way to avoid this post-Brexit is for regulations on both sides to remain more or less the same in key areas including food, animal welfare, medicines and product safety. The 'backstop' in Theresa May's Withdrawal Agreement was intended to address this - stating that if no future trade agreement could be reached between the EU and the UK, then rules and regulations would stay as they are. This has been rejected by Brexit supporters as a 'trap' to keep the UK in the EU's customs union, which would prevent the UK striking its own independent trade deals. There are an estimated 72m road vehicle crossings a year between Northern Ireland and the Republic of Ireland, and about 14% of those crossings are consignments of goods, some of which may cross the border several times before they reach a consumer. Brexit supporters say this can be managed by doing checks on goods away from the border, but critics say it will be difficult to police this without any physical infrastructure like border posts or cameras, which could raise tensions in the divided communities of Ireland.

Interactive: A typical hour in the life of the Irish border Photograph: Design Pics Inc/Design Pics RF

The UK has said that such checks on goods can be carried out at traders’ premises and “designated points”, including potentially government buildings.

The British government is also insisting that the EU rewrites its own customs code to allow greater exemptions for small traders on the island of Ireland from having to fill out customs paperwork.

Dublin has insisted that it will not agree to any deal that involves further such checks and controls on the island of Ireland, given the risk to peace and the economy. Brussels is concerned that changes to its laws will create an open door to smugglers.

Juncker’s response was, nevertheless, littered with positive comments in a sign that the EU does not want to be blamed for a failure to find agreement.

The commission said Juncker had praised Johnson’s “determination” and “acknowledged the positive advances, notably with regards to the full regulatory alignment for all goods and the control of goods entering Northern Ireland from Great Britain”.

Downing Street had briefed before Johnson’s address to the Conservative party conference in Manchester that Johnson would use his platform to make a “final offer” to Brussels, but the rhetoric appeared in the end far more conciliatory than billed.

Johnson instead stressed the UK was making a fair proposal which would avoid extra checks on goods on or near the border and that the EU should “compromise in their turn”. In a letter to Juncker published on Wednesday, Johnson described his proposals as the “broad landing zone”.

It is still hoped in Brussels, that Johnson will come to recognise that the EU cannot accept a proposal that creates a customs border on the island of Ireland due to the risks to the single market, the all-Ireland economy and peace in the region.

Given the UK is proposing a four-year time limit on alignment between Northern Ireland and the EU standards, there is some hope the British government might move on customs too.

The EU is open to a Northern Ireland-only backstop that would keep the province in the customs union and under swathes of single-market legislation. And while there are yet to be discussions on putting a time limit on such an arrangement, EU sources have suggested Dublin could be put under pressure to accept such a deal if it was clear that the Commons would accept it.

The more likely outcome, however, was that there would not be a deal and that the UK would be seeking an extension to its membership beyond 31 October, EU sources suggested.

Michel Barnier, the EU’s chief negotiator, said: “There is progress but, to be frank, a lot of work still needs to be done.”

“This cannot be his last plan,” said one senior source close to the negotiations. “It is unworkable to dissociate customs from the regulatory regime. No point in even considering a time limit on something that is not workable.”

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A second diplomatic source added: “At least he didn’t say in the speech it was his final offer. So we’ll be listening very carefully to see if there’s scope to bring it back somewhere reasonable.”

Following a meeting with the German chancellor, Angela Merkel, in Berlin, Mark Rutte, the Dutch prime minister, said the EU’s member states would “look carefully at the proposals”.

Merkel reiterated the comments but added that it was important that the EU27 stuck together, in an indication that Dublin’s reaction in the coming days will be key. “We trust in Michel Barnier, and we will discuss it further,” she said.

In his speech to the Tory conference, Johnson had described the issue of customs as technical.

Leo Varadkar, the Irish taoiseach, told reporters that his government remained concerned by the UK’s plans. “It’s much more than technical. It’s deeply political, legal, and the technical aspects are a small part of that,” he said.

The DUP has offered its support for the UK proposals but Sinn Féin’s president, Mary Lou McDonald, said the proposals should be thrown out.



“This is not a viable proposal from the British government,” she said. “It is incumbent on the EU and the Irish government to make it absolutely clear that this proposal is absolutely out of the question,.”