ITV News Correspondent Neil Connery explains the latest development
The EU has said it is launching legal action against the UK over its plans to rip up a key Brexit agreement.
Foreign Secretary Liz Truss said on Monday that the UK would be changing large aspects of the Northern Ireland Protocol, an agreement Boris Johnson signed with the EU as part of Britain's Withdrawal Agreement.
The EU's Brexit negotiator, Maroš Šefčovič, said the UK government's Northern Ireland Protocol Bill - which will change the deal - is "extremely damaging to mutual trust and respect between the EU and the UK".
The European Commission vice-president said: "It has created deep uncertainty and casts a shadow over our overall co-operation, all at a time when respect for international agreements has never been more important.
"That is why the Commission has today decided to take legal action against the UK for not complying with significant parts of the protocol on Ireland/Northern Ireland."
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The UK has insisted the unilateral move to rip up the Brexit agreement it made with the EU is legal because of the exceptional way it is impacting Northern Ireland.
Critics say the action not only damages relations with Britain's closest trading partner even further after Brexit but could cause other countries to mistrust the UK and impact its ability to agree other international deals.
Mr Sefcovic said: "Let there be no doubt: there is no legal nor political justification whatsoever for unilaterally changing an international agreement.
"Opening the door to unilaterally changing an international agreement is a breach of international law as well. So let's call a spade a spade: this is illegal."
He also hit out at the UK for signalling it plans to walk out on a deal it signed less than three years ago.
He told reporters in Brussels: "I'm sure the UK government knew perfectly well what they signed up to when they agreed to the protocol - although I have to admit they didn't do a very good job explaining it to the public."
What is the EU's legal action against the UK?
The European Commission said it would launch a series of legal proceedings against the UK, including action initiated last year but shelved to facilitate negotiations on post-Brexit trade.
It related to the UK's unilateral extension of protocol grace periods in 2021, which delayed the protocol's full implementation.
Resuming the proceedings, the EU is issuing the UK with a "reasoned opinion" and giving it two months to respond. If the UK does not respond to the bloc's satisfaction, it will refer the matter to European Court of Justice.
Two other infringement proceedings announced on Wednesday relate to alleged UK failures around Sanitary and Phytosanitary (SPS) checks on agri-food produce entering Northern Ireland from Great Britain.
The EU is issuing formal notices of action in respect of the two new infringement proceedings, alleging that the SPS checks are not being carried out properly, with insufficient staff and infrastructure in place at the border control posts at the ports in Northern Ireland.
The proceedings outlined on Wednesday do not specifically relate to the content of the government's controversial Northern Ireland Protocol Bill.
The EU said any potential proceedings over the Bill would only happen when it was enacted at Westminster.
Prime Minister Johnson insisted the Northern Ireland Protocol Bill contained only minor, bureaucratic changes, while Downing Street said it was an “insurance mechanism” in case a negotiated agreement with the EU could not be found.
The premier of Estonia has told ITV News Political Editor Robert Peston that she thinks the PM 'should be negotiating not breaking international law'
Speaking on Peston, which airs on ITV at 10.45pm, Prime Minister of Estonia Kaja Kallas, asked how she feels about the UK Government’s decision to legislate to overrule the Northern Ireland Protocol, she said: "It is clear that when we have done international agreements, we have to follow those agreements and agreements are always compromises which means there are some parts that we don’t like on both sides.
"But they are agreements. This is one of the values that we have in the Western world that agreements should be followed. ‘Pacta sunt servanda’ in Latin.
"That’s why I think this is a fundamental principle. If there is something that we have to negotiate more to try to make it better, it still requires the consent on both sides because it is an agreement.”
Asked how worried she is that the economic cost felt by the West as a result of the war in Ukraine is leading to war fatigue and could lead to European countries compromising with Russia, said: "I’m very worried about this.
"I see very high inflation that is very much related to the energy crisis and we know that the energy crisis is very much related to gas and fuel coming from Russia.
"So this is causing instability within our society because energy cost is something that affects everybody and everything so this is clearly a great concern.
"And if we move on to the future then we will see that there's more and more of this war fatigue.
"What we have to understand is that we have made this mistake already, three times if you look just to the near history.
"In Georgia, Crimea, Donbass. It was a moment where everybody said okay let’s have a ceasefire, everybody stays where they are and we have the end of conflict.
"What the message to Putin, who only understands strength, was okay I conquered territories, nothing bad happened to me because of that and this aggression paid off.
"If we do this mistake again, even though it’s very painful right now regarding the inflation and all the energy prices and migrants, war refugees coming, then it will just have a much longer effect if Putin goes unpunished."
The UK says there's no reason to sue
Foreign Secretary Truss, who also acts as the UK's chief Brexit negotiator, believes her proposed changes to the Northern Ireland Protocol "don't make the EU any worse off" as the bloc's single market would be protected, "so there simply is no reason for the EU to take any action".
She told ITV News the Good Friday Agreement - a treaty signed in 1998 which helps ensure peace in Northern Ireland - is "being undermined by the way the protocol is operating, that's why we need to change the protocol, that's why it's legal to change the protocol".
She said she prefers a negotiated settlement to amend the protocol but claims she's been forced to move unilaterally because the EU is refusing to change the treaty's text.
The EU says it has made constructive proposals to fix issues with application of the protocol which would work within the current framework of the agreement - which Boris Johnson negotiated and signed in 2019.
The measures within the protocol are aimed at preventing a hard border on the island of Ireland.
But by imposing checks on goods crossing the Irish Sea from Great Britain, it has fuelled unionist anger in Northern Ireland.
The PM on Monday claimed it is "not a big deal" to change the protocol but business leaders have warned of a “damaging trade war” with the EU if Britain presses ahead with ripping up the protocol.
Britain's trade deal with the European Union, signed on December 30, 2020, was agreed with the Northern Ireland Protocol as a foundation to how the two would operate.
Mr Šefčovič said any move to change the protocol is "damaging to mutual trust" and "undermines the trust" that is necessary for the trade deal to work.
A UK government spokesperson said: "It is disappointing that the EU has chosen to relaunch legal proceedings relating to the grace periods currently in place, which are vital to stop the problems caused by the Protocol from getting worse.
"The UK’s preference remains for a negotiated solution but the proposals set out by the EU today are the same proposals we have been discussing for months and would not solve the problems – in many cases they take us backwards from current arrangements.
“The Protocol is undermining the Belfast (Good Friday) Agreement – disrupting trade and leading to people in Northern Ireland being treated differently to the rest of the UK.
"The EU continues to insist it is unwilling to change the Protocol itself, so we are obliged to act ourselves to change the parts of the Protocol that are causing problems.
"The legislation we introduced this week delivers practical, reasonable solutions which also protect the EU single market and support North-South trade."
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A majority of Northern Ireland's lawmakers told Prime Minister Johnson they do not want him to rip up the agreement but the PM says he must appease both republicans and unionists.
What is the UK proposing?
The government wants to make changes so trade between Great Britain and Northern Ireland can flow freely without checks.
The Bill will enable ministers to establish a “green lane” so trusted traders are allowed to move goods from Great Britain to Northern Ireland without checks, as long as the products remain within the UK.
Products being placed on the market in Northern Ireland would be allowed to follow either UK or EU regulations, rather than having to comply with Brussels’ rules.
The legislation would also remove the European Court of Justice as a final arbiter in trade disputes over the protocol, with the function instead handed to independent adjudicators.
The government insisted the Bill was compatible with international law under the “doctrine of necessity” which allows obligations in treaties to be set aside under “certain, very exceptional, limited conditions”.