Prime Minister Boris Johnson urged MPs to back his bill to amend the Withdrawal Agreement with the EU to prevent it creating a “blockade” in the Irish Sea and potentially breaking up the United Kingdom in the process.

Boris Johnson said on Saturday that the Withdrawal Agreement (WA) as it stands would give the EU the power to “carve up our country – to divide it” by creating barriers between Northern Ireland and the rest of the United Kingdom. If the barriers remain after the Brexit transition period then the bloc would retain some power over British laws and regulations.

“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,” Johnson wrote in The Telegraph.

“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,” he added.

The Prime Minister said that his government “never seriously believed” that the EU would negotiate in good faith, going on to argue that the bloc has threatened “to destroy the economic and territorial integrity of the UK.”

“By actively undermining the Union of our country, such an interpretation would seriously endanger peace and stability in Northern Ireland. This interpretation cannot have been the real intention of those who framed the protocol (it certainly wasn’t ours) – and it is therefore vital that we close that option down,” Johnson said.

Mr Johnson called on MPs to stand firm and back Britain’s negotiating team by amending the withdrawal agreement, which he argued was passed when the government had “one hand tied behind our back since Parliament had voted to deprive the UK side of the right to walk away”.

“We must get this Bill through. So I say to my fellow parliamentarians that we cannot go back to the dark days of last year – the squabbling that so undermined our negotiators. 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.

The Internal Market Bill would give the British government the ability to disapply sections of the Withdrawal Agreement that would create trade barriers between Northern Ireland and the rest of the United Kingdom would also prevent EU restrictions on state aid in Northern Ireland being enforced on the British mainland.

The EU has accused Britain of breaching international law with the bill, and is considering taking legal action to introduce sanctions should the two sides fail to reach a deal.

In response to Mr Johnson’s claim that the EU is seeking to undermine the integrity of the British Union, eurocrat Guy Verhofstadt said on Saturday: “The real threats to the integrity of the UK are you Boris Johnson and your Brexit! It was your choice to choose the hardest possible exit. Why did you not explain the consequences of your plan to the British people?”

Slovakian diplomat, Maroš Šefčovič, a former communist and Michael Gove’s counterpart on the Withdrawal Agreement (WA) joint committee, said: “The Withdrawal Agreement is not open for renegotiation and we expect the letter and the spirit of the Withdrawal Agreement will be fully respected. I think on that we have to be very, very clear.”

The President of the European Commission, Ursula von der Leyen, said that she was “very concerned” about the Internal Market Bill, adding that it “breaks international law and undermines trust.”

On Friday, Brexit Party leader Nigel Farage called for the WA to be abandoned altogether, saying that it was “always rotten” and that the terms of the deal “could effectively mean the end of the UK as a single entity”.

“Make no mistake, this is a mess of the Government’s own making but the fact that they are now insisting that we are to become an independent country is to be warmly welcomed,” Farage added.

“As Brussels looks pretty unlikely to change any of the documents, perhaps the time has come for us to ditch the Withdrawal Agreement as it currently stands… if Mr Barnier thinks he can trap Britain into Brussels’ rather inept orbit then he has another thing coming.”

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