The Republic of Ireland is the second highest gross domestic product per capita in the EU after Luxembourg, thanks to a favourable corporate tax system and membership of the European single market.  About 85% of Ireland`s freight exports worldwide are from ports in the UK, about half of which are destined for the UK, while half continue to the EU via Dover and Calais.  The UK`s use as a “land bridge” is rapid (it takes 10.5 hours for the Dublin-Holyhead-Dover-Calais route), but could be compromised by customs checks in Wales and Calais in a Brexit without agreement. Indeed, in the absence of trade agreements, the trade relationship between the United Kingdom and the EU (including the Republic) would amount to membership of the World Trade Organization (WTO). They stipulate that the same tariffs and tariffs must be applied indiscriminately among all WTO members (the most favoured nation`s criterion), unless some members have a trade agreement.  This principle would also apply to trade across land borders in Ireland in the absence of a trade agreement. On 10 October 2019, Mr Johnson and Leo Varadkar held “very positive and promising” talks that led to the resumption of negotiations and a week later Mr Johnson and Jean-Claude Juncker announced that they had agreed (subject to ratification) on a new withdrawal agreement replacing the backstop with a new protocol on Northern Ireland.2  Negotiations between civil servants resulted in a draft agreement to be finalised at a meeting between Jean-Claude Juncker and Theresa May on 4 December 2017 in Brussels. There has been progress in financial settlement and civil rights, but the meeting was interrupted after the Northern Ireland Democratic Unionist Party opposed agreements for the Irish border.  Negotiators from the United Kingdom and the European Union agreed on the principle of a new protocol on Ireland and Northern Ireland and on political declaration. Meanwhile, Irish Foreign Minister Simon Coveney said the deal was good news. This protocol was strongly rejected by the Democratic Unionist Party, which saw it as a weakening of Northern Ireland`s place in the United Kingdom and is seen by a number of commentators as the main reason why the withdrawal agreement was not ratified by the United Kingdom Parliament.    Since 2018, the DUP has stated that the anti-Northern Ireland ruling must be withdrawn from the Brexit withdrawal agreement if it were to continue to support the Conservative government in the House of Commons although the party has stated that it is open to limiting backstops over time.
 In a joint statement, the UK and the EU said that an “agreement in principle” had been reached on all issues. Mr Coveney said: “This positive development follows a significant and productive commitment between the EU and the UK in the implementation of the protocol, as envisaged in the withdrawal agreement. The Northern Ireland Protocol, negotiated by British Prime Minister Boris Johnson last October, is part of the withdrawal agreement (which some have called a “divorce agreement”) in which the UK left the EU on 31 January 2020. The declared means of the protocol for achieving the objectives (referring to the internal market of the European Union and the customs union) are defined three later paragraphs of the same page: the protocol on Northern Ireland must be welcomed in some respects.