Boris Johnson has accused Brussels of threatening to impose a trade border in the Irish Sea which would “destroy the economic and territorial integrity of the UK”.
The prime minister claimed in an article in the Daily Telegraph that the European Union could “carve up our country” unless MPs pass legislation allowing him to override parts of his own Brexit deal.
He also argued that the UK Internal Market Bill – which ministers admit breaks international law – was “crucial for peace and for the Union itself” and would improve the chances of agreeing a “Canada-style” trade deal with Brussels.
It comes after senior Tories vowed to vote against the legislation or amend its most controversial provisions, and the EU threatened to take legal action unless Mr Johnson backed down by the end of the month.
In the article, Mr Johnson claimed that his negotiators had discovered there “may be a serious misunderstanding about the terms” of the withdrawal agreement he signed last year.
“We are now hearing that unless we agree to the EU’s terms, the EU will use an extreme interpretation of the Northern Ireland protocol to impose a full-scale trade border down the Irish sea,” the prime minister wrote.
“We are being told that the EU will not only impose tariffs on goods moving from Great Britain to Northern Ireland, but that they might actually stop the transport of food products from GB to NI.
“I have to say that we never seriously believed that the EU would be willing to use a treaty, negotiated in good faith, to blockade one part of the UK, to cut it off; or that they would actually threaten to destroy the economic and territorial integrity of the UK.”
The prime minister added: “If we fail to pass this Bill, or if we weaken its protections, then we will in fact reduce the chances of getting that Canada-style deal,” he wrote.”Let’s remove this danger to the very fabric of the United Kingdom. Let’s make the EU take their threats off the table.
“And let’s get this bill through, back up our negotiators, and protect our country.”
However, both Ireland and the EU have warned that the Bill poses a serious risk to the peace process and the Good Friday Agreement.
Ireland’s deputy prime minister Leo Varadkar said he believed Mr Johnson’s plans were “brinkmanship and sabre rattling” but added that there could not be a trade agreement with the EU in “circumstances where the UK government is not honouring the withdrawal agreement”.
Three former UK prime ministers – Theresa May, Gordon Brown and Sir John Major – have also condemned the bill as a “huge act of self-harm”.
Additional reporting by Press Association