Up to eight ministers fear being bounced into giving their consent without knowing how difficult it will be for the UK to later break free from the EU customs union, The Independent understands.
“It’s basically the Pizza Club plus Sajid Javid,” a source said – referring to an earlier private gathering of seven pro-Brexit ministers, with the home secretary also expressing the same fears.
Michael Gove, the environment secretary, led the call, at cabinet on Tuesday, after the prime minister indicated only a legal summary would be made available.
After the invasion, it was revealed that the full advice warned a court “might well conclude” it was illegal under international law and trigger legal action against members of the armed forces.
Concerns rose on Tuesday when Geoffrey Cox, the attorney general, gave a defence of the proposed deal that was largely “political opinion” rather than a legal judgement, it is said.
The QC advised that a UK demand for the unilateral right to end the “backstop” – which would keep the UK in the customs territory until there is an alternative solution to avoid Irish border checks – could be dropped.
However, he is understood to have largely argued that was necessary as the only way to secure an agreement with the EU this month, rather than on the basis of how much power Britain would be giving up.
Mr Cox also acknowledged Northern Ireland would be under different regulations without, the pro-Brexit ministers believe, setting out the full legal implications of that.
“They believe the cabinet shouldn’t be palmed off with a summary, but must see the full legal advice unfettered by political opinion,” said a source close to one concerned cabinet minister.
“Michael was speaking for himself when he made the call, but the other ministers quickly nodded their agreement.”
A second cabinet level source confirmed the environment secretary was backed by other ministers, saying: “Gove isn’t alone in this.”
The “pizza club” meeting, last month, was also attended by Dominic Raab, the Brexit secretary and Liz Truss, the Treasury chief secretary, and was hosted by Commons leader Andrea Leadsom.
At cabinet, Mr Cox, crucially, claimed agreeing to a mutual review of the backstop would not give the EU a veto – and that even a unilateral mechanism would require a ruling from another body.
Meanwhile, the Democratic Unionist Party, which is propping up the Tories in power, called for the full legal advice to be published to parliament.
“If the House of Commons is going to have a meaningful vote on a deal upon which this legal advice is very important, then I think people are entitled to know what that legal advice is,” said Jeffrey Donaldson, the DUP’s chief whip at Westminster.
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