Britain and the European Union reached a tentative Brexit deal on Thursday as part of their three-year-long divorce, but the agreement was almost immediately rejected by the U.K.’s main opposition and other key allies, throwing the plan into doubt.
Among the main sticking points is the so-called “Irish backstop” — a provision designed to prevent the reintroduction of a hard border between Northern Ireland, which is part of the U.K., and the Republic of Ireland, a member of the EU.
Here is a brief recap of why the backstop has roiled Brexit negotiations and how the U.K. could be moving towards an “Irish sea border.”
Why a border is a problem
Decades of fighting in Northern Ireland between Irish nationalists and U.K. unionists and the British government saw nearly 4,000 killed from 1968 to 1998.
During that time, known as “the Troubles,” a border heavily patrolled by soldiers and paramilitary groups divided the country. The 1998 Good Friday accord helped stop the fighting and led to the end of a land border between Ireland and Northern Ireland.
Britain and Ireland are currently part of the European Union’s single market, which allows people and goods to flow freely between Ireland and Northern Ireland with no need for checks. Brexit could disrupt that flow of goods, damaging businesses and potentially threatening peace in the region.
In an interview with Channel 4 News Wednesday, the New IRA – a paramilitary group which aims to bring about a united Ireland – has said that any border infrastructure would be a “legitimate target for attack.”
What is the “Irish backstop”?
To prevent a hard border on the island of Ireland, the proposed withdrawal agreement put forth by former prime minister Theresa May included a “backstop” provision that would keep goods and people flowing freely across the border between EU member Ireland and the U.K.’s Northern Ireland after Brexit.
Under the original proposal from the EU and May, Northern Ireland alone would remain in the EU’s single market and customs union, leaving England, Scotland and Wales free to create their own trade deals.
But Northern Ireland’s Democratic Unionist Party, which supported May’s minority Conservative government, objected to the idea, saying it would see Northern Ireland treated differently and could threaten the union.
What is the “Irish sea border?”
Prime Minister Boris Johnson has insisted that all of the U.K. must leave the EU’s customs union and has proposed the idea of a “single regulatory zone” on the island of Ireland.
Under the new agreement, customs checks would be carried out before goods enter or leave Northern Ireland. This effectively means creating checkpoints at major ports in Great Britain and Northern Ireland like Liverpool, Belfast and Larne.
The idea behind this proposal is that if goods are checked before entering the country then cross-border trade can continue to flow across Ireland. All companies moving goods to Northern Ireland would be affected by the plan, and some business groups have warned it would create unnecessary red tape and could be crippling to the region’s economy and hurt small businesses.
According to the Guardian, about $2.6 billion worth of trade and services flowed from Great Britain to Northern Ireland in 2018.
Who is opposed to the idea?
The U.K.’s main opposition Labour Party and the DUP — a key Johnson ally — quickly opposed the provisional deal.
DUP Leader Arlene Foster said Thursday the party “could not support what is being suggested on customs and consent issues.”
Labour Party Leader Jeremy Corbyn blasted the revised deal, saying it’s “even worse” than the settlement reached by May’s government that was repeatedly rejected by British lawmakers.
“From what we know, it seems the prime minister has negotiated an even worse deal than Theresa May’s, which was overwhelmingly rejected,” Corbyn said in a statement.
Brexit Party Leader Nigel Farage also urged the U.K. Parliament to reject the new deal, saying it is “just not Brexit” and would bind Britain to the EU in too many ways.
What is new about this deal?
The EU has shifted its position by allowing Northern Ireland special access to its single market and giving it a say over the rules, something that was missing from May’s previously rejected agreement. After four years, the Northern Ireland Assembly will vote on whether to continue the arrangement or end it.
Johnson took office in July vowing that Britain would finally leave the EU on Oct. 31 with or without a deal. He has called the agreement a “great new deal” and urged U.K. lawmakers to ratify it in a special session being held Saturday.
— With files from the Associated Press