According to the accounts of EU officials quoted in the Financial Times, Mr Johnson appeared not to understand that his proposals for Northern Ireland to stick to EU food and livestock regulations after Brexit would not resolve the ongoing impasse over customs arrangements at the border.
An official described Mr Johnson “slumping” in his chair at the lunch in Luxembourg as his Brussels counterparts said that the plan for common “sanitary and phytosanitary” (SPS) rules on the island of Ireland would not do away with the need for customs checks on the vast majority of goods crossing the border.
According to the FT, one official said the PM turned to chief negotiator David Frost and Brexit secretary Stephen Barclay and said: “So you’re telling me the SPS plan doesn’t solve the customs problem?”
There was no immediate response from Downing Street to the report.
But Labour MP Ian Murray, a supporter of the People’s Vote campaign for a second EU referendum, said: “Reports that Johnson doesn’t understand even the basics about cross-border trade and customs are shocking and deeply worrying.
“In just a few weeks he plans to force us out of the EU, either with no deal or a very bad deal and he doesn’t even know what that will mean for Ireland or, presumably, trade with the rest of the EU.
“Out-of-his-depth does not even come close to describing how apparently clueless he is.
“We cannot let this man decide our fate. We must let the people decide in a final say referendum.”
Mr Johnson has yet to put forward concrete proposals for post-Brexit arrangements in Ireland to do away with the need for the controversial backstop, which he insists must be removed from any withdrawal agreement.
As well as the all-Ireland single market for agrifoods, he is understood to be suggesting that there should be no form of customs union between the UK or Northern Ireland and the remaining EU and that customs and standards checks on goods should be carried out away from the Irish border.
More controversially, he is believed to be floating a “Stormont lock” giving the people of Northern Ireland the right to withdraw their consent to changes to rules on agriculture.
With the 30-day period for new proposals suggested by German chancellor Angela Merkel now almost over, EU chief negotiator Michel Barnier today told the European Parliament it was time for the PM to stop “pretending to negotiate”.
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