The EU's chief negotiator has rejected a major component of the UK's proposal around a temporary customs arrangement, saying it cannot apply to the whole of the UK.
Speaking from Brussels this afternoon Michel Barnier said: "Our backstop cannot be applied to the whole of the UK… What is feasible for a territory the size of Northern Ireland is not feasible for a territory the size of the United Kingdom."
But he also insisted that there be common rules across the island of Ireland.
Barnier's position means the likelihood of a border down the Irish sea – with Northern Ireland remaining in the customs union while the rest of the United Kingdom is outside it – has not gone away, despite UK Prime Minister Theresa May categorically rejecting it as unacceptable.
He also suggested the time-limited nature of the agreement – a key factor in May getting approval from her Brexiter Cabinet ministers – might prevent Brussels from waving it through.
Barnier said: "The other issue is how temporary it would be – backstop means backstop… This has to be a backstop that provides a guarantee under all circumstances."
He added that May "for whom I have great respect, and I continue to have great respect" had already agreed the basic terms of a backstop in March, "and there's no question of back-tracking on that".
While he acknowledged the team was still working out a full response to the document, which was published yesterday afternoon some hours after it was expected, Barnier indicated that there would be no major breakthrough at the June European Council meeting later this month.
Asked about comments made by foreign secretary Boris Johnson earlier this week, Barnier said he tried to remain calm, adding: "We respect the British red lines. It would be perhaps good if the British could respect their own red lines."
But if the UK were to adjust their red lines, the EU would adjust its offer.
More to follow…