The author was an economic adviser to French Prime Minister Michel Rocard in 1998, when Rocard negotiated an agreement to restore civil peace in New Caledonia, in the Southwest Pacific. The UK government has said Brexit will not mean a return to the hard border.  According to Theresa May, then Prime Minister of the United Kingdom, and Irish Prime Minister Enda Kenny in 2016, this agreement should be maintained after the UK`s withdrawal from the EU.  Any new border within these islands will be extremely problematic. The backstop of insurance from the EU is useful, but does not meet the challenge. The least bad situation is that the UK as a whole chooses to remain in a customs union with the EU and, if not the whole of the United Kingdom, Northern Ireland as a region, in the internal market. This approach would be consistent with the Good Friday agreement, including the principle of approval, and would be implemented by decentralized structures. The agreement also concerns the United Kingdom and Ireland as « partners in the European Union, » and it was claimed in R (Miller) against the Secretary of State for Leaving the European Union that the agreement meant that the approval of Northern Ireland voters had to leave the European Union (Brexit). The UK Supreme Court unanimously ruled that this was not the case, but the agreement nevertheless strongly marked the form of Brexit. After the UK`s total withdrawal from the EU, the CFP will no longer apply to its waters; The United Kingdom will have exclusive control under the UN Convention on the Law of the Sea of persons authorized to fish its waters.  Many British fishermen supported Brexit in order to get out of the CFP and what it considered to be an extreme preference, from fishermen from other countries who, in many cases, depend on the rich fisheries around the British Isles for species highly sought after in their markets, but despised by most British consumers. They want the British government to fully exercise this power, by limiting or locking all EU ships out of their waters until an agreement is in its favour.
 Instead, the agreement found a creative path by allowing a form of co-sovereignty. The Good Friday agreement allowed Northern Irish to identify themselves as Irish, British or both and to have a passport from one or both countries. The British government is virtually out of the game and neither parliament nor the British people have, as part of this agreement, the legal right to obstruct the achievement of Irish unity if it had the consent of the people of the North and The South… Our nation is and will remain a nation of 32 circles. Antrim and Down are and will remain a part of Ireland, just like any southern county.  Good Friday Agreement (GFA) or Belfast Agreement (Irish: Comhaonté Aoine an Chéasta or Comhaonté Bhéal Feirste; Ulster-Scots: Guid Friday Greeance or Bilfawst Greeance) is a couple of agreements signed on 10 April 1998 that put an end to most of the violence of the Troubles, a political conflict in Northern Ireland that had erupted since the late 1960s. This was an important development in the Northern Ireland peace process in the 1990s. Northern Ireland`s current system of de-decentralized government is based on the agreement. The agreement also created a number of institutions between Northern Ireland and the Republic of Ireland, as well as between the Republic of Ireland and the United Kingdom.