The return of violence to Northern Ireland is a potential consequence if we get the Brexit talks wrong, Irish Prime Minister Leo Varadkar stated.
"There's merit in discussing the idea of a longer transition, but that cannot be an alternative to the backstop on Ireland," Varadkar told reporters ahead of an EU summit on Brexit.
Varadkar added that working out all the details of the deal on the EU-UK relationship could take more than two years.
According to media reports, chief EU Brexit negotiator Michel Barnier will propose the extension to UK Prime Minister Theresa May in exchange for her agreeing to a two-stage deal that would include a separate backstop for Northern Ireland to keep it as part of the EU customs union and single market for goods, as well as a UK-wide customs solution.
Unresolved Irish Border Issue Leaves EU-UK Brexit Deal Possible, Not Certain
Reaching an agreement between the United Kingdom and the European Union on the UK withdrawal from the bloc is possible, but there is no certainty on this issue, as the Irish border still remains an unresolved matter, EU chief Brexit negotiator Michel Barnier said in an interview for a French radio station.
"I believe that we need the agreement, but I am still not sure that we will get it. It is difficult yet possible," Barnier told France Inter.
He specified that the Brexit agreement was ready by 90 percent.
"This is a huge job that my team has been doing for one year and a half for the benefit of the 27 EU states, and the European Parliament. We have been doing it with the United Kingdom, [the agreement is] not against it, but [we have been working on the agreement] with it [London]. And now the issue of Ireland remains open," Barnier added.
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One of the key issues to settle the withdrawal agreement is that of the border in Northern Ireland, separating it from the Republic of Ireland.
London and Brussels have acknowledged that there should be a sort of safety net in place if the agreement on EU-UK partnership does not ensure that this border remains frictionless. However, the two sides differ in their approach to the backstop.
UK Prime Minister Theresa May has objected to the plan as it would create a border between Northern Ireland and the rest of the United Kingdom.
Such a border would violate the Good Friday Agreement (GFA) or Belfast Agreement that Northern Ireland's present devolved system of government is based on. The agreement also created a number of institutions between Northern Ireland and the Republic of Ireland, and between the Republic of Ireland and the United Kingdom.
From October 17 through October 18, leaders of the 27 EU states conducted a European Council meeting focused on Brexit.
They concluded that the progress in the EU-UK Brexit talks was not sufficient in spite of multiple negotiations on the matter.