Brussels has warned Britain against using the Northern Ireland peace process as a “bargaining chip” to secure a UK-EU trade deal, dismissing London’s “magical thinking” on how to manage Brexit.

The admonishment from senior EU officials came ahead of the third round of Brexit talks in Brussels next week, which will open with little hope of a breakthrough, and follows the release of seven negotiating papers this month by Whitehall aimed at injecting urgency into the talks.

“We are concerned by the linkages created in the UK paper on Ireland between the preservation of the peace process, including the invisible border [between Northern Ireland and the Irish Republic], and the future of the EU-UK trade relationship,” said a senior EU official. “The peace process must not be a bargaining chip in these negotiations.”

The increasing cross-channel sniping nearly six months into the two-year Brexit process has begun to unsettle negotiating teams on both sides, with EU officials increasingly sceptical that “sufficient progress” will be made by October to move from divorce negotiations to talks on a future trade relationship, as had been planned.

For their part, British officials believe the European Commission is being inflexible by rejecting UK attempts to push trade-related issues on to the agenda through the recently-published position papers.

The decision to leave the EU is the UK’s decision. It was not the decision of Ireland, it was not the decision of the EU. So the UK has to take responsibility

EU negotiators were particularly annoyed by the UK position paper on Ireland, which suggested resolving the issues surrounding Northern Ireland through a UK-EU trade deal on areas like agriculture and electricity that effectively replicated the benefits of the EU single market Britain wants to leave. Both the EU and the UK want to avoid a hard border with the Republic of Ireland when the UK leaves the EU in 2019.

“The decision to leave the EU is the UK’s decision,” added the EU official. “It was not the decision of Ireland, it was not the decision of the EU. So the UK has to take responsibility for the implications of that.”

Added the official: “If you look at the Ireland paper, it is very good on aspirations . . . but it is short on workable solutions.”

David Davis, the Brexit secretary, has said it is “wholly illogical” for the EU to imagine it can resolve border issues in Ireland without knowing what future trade and customs relations will be.

The dispute has left the region without a voice in Brexit talks that will have a significant impact on Northern Ireland’s economy and on the border with the Republic of Ireland © Getty

The UK official said London looked forward to reading the commission’s response on Northern Ireland. “This is not some sort of game with bargaining chips,” the official said.

Officials in Brussels questioned how the UK could push for continuing EU funding tied to the peace process while Downing Street remained unwilling to agree the size of its financial obligations to the EU after Brexit.

Britain’s Brexit bill remains the biggest impediment to an early deal on divorce terms, and EU negotiators are seeking to push the UK to move by holding firm against trade discussions.

The British ideas to maintain “frictionless” trade across the Northern Irish border through technological innovation have been met with incredulity in Brussels.

“The technical cannot outpace the political. We are not yet there in terms of the political debate and the full realisation of the implications of [Brexit] on Northern Ireland,” said the senior EU official.

“This is not the moment to talk about technical, let alone technological solutions . . . what we see in the UK paper is a lot of magical thinking about how an invisible border could work in the future.”

Asked whether October was a realistic timeframe to make “sufficient progress” on divorce issues, the senior EU official said: “When you look at where we are and where we need to be, it is a big gap. In the next round it is unlikely that we will make much progress in closing the gap. There is no deadline for making sufficient progress.”

A spokesman for the Department for Exiting the EU said on Friday night: “We have always been clear about the importance we attach to Northern Ireland and the Good Friday Agreement — and to the lives and livelihoods of the people of Northern Ireland.

“There have been decades of progress to achieve peace in Northern Ireland which is why the UK has put forward a detailed position paper that puts protecting the Good Friday Agreement at the heart of our approach.

“That includes a proposal that the UK and EU should agree upfront on the crucial importance of avoiding a hard border for the peace process in Northern Ireland.”

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