BORIS Johnson’s plans to unilaterally ditch the post-Brexit deal with the European Union would be a “historic low point” between Ireland and the UK, the Taoiseach has warned. 

In a speech to the European Parliament, Michael Martin said any overriding of the Northern Ireland protocol would be “to the benefit of absolutely no-one”.

It is not clear when the government will bring forward new legislation. It had been expected in the Commons today, but it has reportedly been delayed by the fall-out from the no-confidence vote in the Prime Minister. 

The protocol - which was part of the UK’s 2019 Brexit deal with the EU - prevents a trade and customs border between the north and south of Ireland by effectively placing one between Great Britain and Northern Ireland.

It means there are checks on some goods entering Northern Ireland from Great Britain, but none between Northern Ireland and what is ultimately the EU. 

The new law would, if passed, likely unilaterally suspend or change that agreement by scrapping the checks on food and goods moving from Great Britain to Northern Ireland.

The problem for Downing Street and Northern Ireland's unionists is that there needs to be a trade and customs border between the EU and the UK somewhere. Placing one between the north and south of Ireland would be in breach of the Good Friday Agreement.  

Speaking to Ireland’s RTE, the UK government’s Northern Ireland Minister Conor Burns said the details of the government's plans will be published soon.

He said that the protocol had led to “ridiculously excessive” checks on goods moving within the United Kingdom’s internal market.

“We recognise the attractiveness of the protocol and the place that leaves Northern Ireland in, but the reality is that we have now got ridiculously excessive checks on goods that are moving within the United Kingdom’s internal market that will never go near the Irish Republic, that are absolutely no threat whatsoever to the integrity of the Single Market.”

He criticised the lack of flexibility from Brussels: “It’s a very, very simple proposition here. We’re simply saying the goods moving within our own country – with the exception of live animals, which we can see the need for checks on, obviously – the goods moving within our own country should move freely.

“They pose no risk whatsoever.

“We are very clear that the proposals that we will put forward, the legislation that we will put to Parliament, will absolutely be lawful and appropriate.”

In his address on Wednesday morning to the European Parliament, Mr Martin said that would mean the UK ignoring its obligations under international law.

“It would mark a historic low point, signalling a disregard for essential principles of laws, which are the foundation of international relations,” he said.

“And it would quite literally be to the benefit of absolutely no one. Without a spirit of partnership there would have been no peace process in Northern Ireland.

“Without trust, without engagement, without a willingness to see things from the point of view of others, there would have been no Good Friday agreement, nor quarter of a century of peace in Northern Ireland in which young people have been able to grow and to flourish as themselves …

“What was so hard-won as we look across our continent, as we see what is at stake when the rule of international law is threatened – it falls to all of us to work together and to stand by what we have agreed.”

Mr Martin accused the UK government of "bad faith efforts to undermine a treaty freely entered into instead of trying to create a constructive atmosphere for all to engage."

“I have said many times that there are solutions to practical problems under the protocol if there is a political will to find them. But that requires partnership. It requires the United Kingdom government to engage with good faith, seriousness and commitment,” he added.

The proposed legislation could ultimately end up being one of the first clashes between Mr Johnson and the 148 Tory backbenchers who called on him to resign. 

On Monday, the Conservative MP Jesse Norman, an influential former Treasury minister, said the possible breaching of the Northern Ireland protocol was one of the reasons why he could not support the Prime Minister.

He said it would be “economically very damaging, politically foolhardy, and almost certainly illegal”.