Boris Johnson has been told that the majority of Northern Ireland assembly members reject the government’s “reckless new protocol legislation”.
A letter on behalf of 52 of the 90 members of the legislative assembly (MLAs) said the proposal “flies in the face of the expressed wishes of not just most businesses, but most people in Northern Ireland”.
It comes as the government prepares to table legislation in the UK parliament to override parts of the Northern Ireland Protocol – despite claims that the move will breach international law and fears that it could start a trade war with the EU.
The prime minister said it would be “preposterous” and a “gross, gross overreaction” for Brussels to respond in such a way to what he described as the “trivial” planned changes.
Ministers have said all parties in Northern Ireland recognise there are problems with the protocol, which is designed to prevent a hard border with the Republic of Ireland but effectively creates a border in the Irish Sea with goods imported from Britain subject to customs checks.
The DUP has refused to support power sharing until the issues are resolved.
But the letter from the MLAs – representing Sinn Fein, the SDLP and the Alliance Party but not the unionist DUP or UUP – to the PM, said the protocol “is itself a product of the hard Brexit you personally championed and a withdrawal deal you personally signed”.
“Whilst not ideal, the protocol currently represents the only available protections for Northern Ireland from the worst impacts of that hard Brexit,” they said.
The letter said the government’s argument that it was acting to protect the Good Friday Agreement was a “grotesque act of political distortion”.
Ireland’s foreign minister Simon Coveney and European Commission vice president Maros Sefcovic both reiterated their opposition to the legislation after each speaking to Foreign Secretary Liz Truss.
A spokesman for Mr Coveney, who held a 12-minute conversation with Ms Truss on Monday, said it “marks a particular low point in the UK’s approach to Brexit”.
Mr Sefcovic said in a tweet that unilateral action by the UK was “damaging to mutual trust and a formula for uncertainty”.
But in an interview with LBC, Mr Johnson said: “It’s a bureaucratic change that needs to be made. Frankly it’s a relatively trivial set of adjustments.”
The prime minister told broadcasters: “We’ve got a problem at the moment, which is… the government of Northern Ireland can’t meet because of the effects of the protocol.
“What it does is it creates unnecessary barriers on trade east-west.
“What we can do is fix that. It’s not a big deal, we can fix it in such a way as to remove those bureaucratic barriers but without putting up barriers on trade moving north-south in the island of Ireland as well.”
Sir Philip Rycroft, the former permanent secretary at the Department for Exiting the EU, told Sky News that Britain’s trading relationship with Europe could be in jeopardy if the government continues with its current approach.
He said: “There is a risk of a full blown trade war with the EU, which would result in the EU withdrawing not just from the protocol but the whole trade and cooperation agreement – and given the state of the UK economy that is the last thing we need.”
Labour leader Sir Keir Starmer, speaking to broadcasters on Monday, said the government was “going down the wrong track”.
“The answer to this is to accept there are some problems in the way the protocol works but they could be resolved around the negotiating table – with statecraft, with guile, with trust,” Sir Keir said.
“Unfortunately we don’t have those in the current prime minister.”
Ms Truss said on Monday after her discussions with Mr Sefcovic to discuss the legislation that the UK still wanted to see a negotiated solution but that “the EU must be willing to change the protocol itself”.
Earlier, Environment Secretary George Eustice rejected the claims of those who say that the protocol is working, suggesting that was only because the deal had still not been implemented in full.
Asked about concerns raised by the CBI that a battle over the protocol with the EU will hurt the economy, he said: “I work very closely with lots of different businesses.
“The truth is that most of the major retailers – like Marks & Spencer and Tesco and others, who are sending quite complex, composite loads to Northern Ireland – they know that the protocol if implemented in its full way wouldn’t allow their business models to really continue.
“So businesses generally do want us to sort this problem out.”
Ms Truss last month laid out the plan for legislation to override parts of the protocol, citing the need to respond to the “very grave and serious situation”.
She said the bill would preserve elements that were working, while fixing those that were not – the movement of goods, goods regulation, VAT, subsidy control and governance.
It could allow ministers to remove customs processes for goods moving within the United Kingdom and enable the frictionless movement of agri-food goods staying within the UK.
It could also see businesses in Northern Ireland given the ability to choose whether to follow UK or EU regulations, depending on who they are trading with.