AN Irish border would be the UK’s only land frontier with the EU after Brexit.
The question of how it is kept open has become a major hurdle in Britain’s bid to quit the bloc. Here’s what you need to know.
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What would an Irish Border look like after Brexit?
Britain, Ireland and the EU all say they want to avoid physical checks on the border.
It was marked by military checkpoints before a 1998 peace deal ended three decades of violence costing around 3,600 lives.
Currently the border between Northern Ireland and the Republic is open with no checks on goods or people.
Ireland and the UK are in a “common travel area” of passport-free movement.
And as they are both in the EU single market, there is no restriction on goods and no tariffs.
Fears have been raised a so-called Hard Border could spark a return to violence, would harm businesses on either side of the border, and would make travelling difficult.
If the UK leaves the customs union and the single market that could mean goods would have to be checked as they crossed the frontier.
And in the event of a no deal, it would be difficult to remain in the single market and keep the border open.
What is the Brexit backstop and what would it mean for the Irish border?
Thebackstop planis essentially a safety net if there is no Brexit trade deal.
It would avoid a hard border between Northern Ireland and the Republic of Ireland.
Also, it would ensure that no “tariffs, quotas, rules of origin or customs processes” would be applied to UK-EU trade.
But it is unclear if the UK would be able to strike free trade agreements with other countries while the backstop endured.
And it is feared the UK would end up being trapped in the customs union.