After Brexit becomes a reality in 2019, there will be two options available to the UK: a hard or a soft border.
A hard border would see the reintroduction of cameras at checkpoints, and all vehicles being stopped as they approach the numerous crossing points.
The other option is for the current situation to endure, whereby vehicles, goods and people can freely pass through a porous border.
The department for exiting the EU told The National that the "worst case scenario would be the hard border", and implied that the British government was looking for a "resolution of the border issue that allows for unfettered trade and access".
As it stands, there is complete freedom of movement between Northern Ireland and the Irish Republic. The border is barely recognised, with minor road markings being the only sign that you are moving between nation states.
The introduction of a hard border would have massive implications for business and personal travel between Northern Ireland.
There has been an understanding between Britain and Ireland for decades that has led to this de facto agreement which has served both countries well for years.
British civil servants stressed to The National how much they wanted to retain the current situation, recognising that anything other than the current status would be troublesome for all concerned.
_________________________________________________
Read more:
[ UK Brexit paper insists there should be no hard Irish border ]
[ UK outlines post-Brexit free and frictionless border plans ]