The EU would help the UK abandon Brexit if it changed its mind, according to the Labour MP Chuka Umunna, who has held private talks with most EU governments.

In a new weekly column for The Independent, Mr Umunna said the 27 EU members saw Brexit as a “damage limitation” exercise and did not want to punish the UK, as some Brexiteers claim. “They believe Brexit is bad for them and us,” he wrote. “If, when we see what the Brexit deal actually looks like, we want to change our minds and fight to reform the EU from within, they would be delighted.”

Dismissing claims by some lawyers that the exit process could not be halted, he added: “There is unanimous acceptance that Article 50 is revocable and they would be very very happy for the UK to continue as a member of the club. That is why it makes sense to keep an open mind on what we do at the end of these negotiations.”

Mr Umunna, who met EU government representatives in recent months as co-chair of the all-party Parliamentary Group on EU Relations, revealed that some officials privately describe the Government’s view of the EU’s position as a “fantasy” and a “delusion.”

He warned the UK will not be able to “have its cake and eat it,” saying: “The problem is that most EU governments are not clear what May thinks a bespoke UK arrangement would look like.” He said no diplomat he had spoken to believes it would be possible to strike a trade agreement by the time a two-year transitional period ends in 2021.

One senior EU representative told Mr Umunna the UK lacks “a national position” on how to approach Brexit. He said EU members had noted the “backseat driving” by Brexiteers ministers such as Boris Johnson and Michael Gove as they undermined Ms May by setting out their own “red lines.”

The former Shadow Business Secretary contrasted the Government’s “incoherence” with “the iron discipline” of the EU27 in the talks. He said the Prime Minister’s charm offensive, including one-to-one dinners with EU leaders, in Downing Street has in the main been rebuffed.

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