Brexit position papers to be released this week risk fuelling tension between the British and Irish governments.
Ireland’s Prime Minister, Leo Varadkar, had urged Theresa May to remain in the customs union to avoid border checks.
But cabinet ministers Philip Hammond and Liam Fox have clearly indicated the UK’s intention to ignore that plea.
The British Government believes a “light touch border”, using some checks and new technology, will solve the problem.
In fields which straddle the Irish border, they risk having some animals in the EU and others outside it.
Image: Can you spot it? There’s no obvious sign of the Irish border along most of its length
Fermanagh farmer John Sheridan says Theresa May’s proposals amount to “a hard border by stealth”.
“We have got rid of that for the last 20 years so to bring that back, you’re just putting a sledgehammer in the centre of a community,” he argued.
People travel freely between Belcoo in Northern Ireland and Blacklion in the Republic, one of multiple crossing points.
Women living on either side have placed cushions on the bridge, literally “softening the border” in protest at any plans for customs posts here.
Image: This border point has been made particularly soft by the addition of cushions
Visual artist Rita Duffy explained: “It cannot be secured, tightened or, as Donald Trump would suggest, walls built.
“When you’re standing in the beautiful landscape, wild and free, and then you think hard border? It simply can’t be allowed to happen.”
Border checks are not optional for a country outside the customs union. They are required under EU law.
So authorities will have to find a way to monitor the 310-mile long border and its network of up to 200 invisible crossing points.
Owen Patterson MP, a former Northern Ireland secretary, believes the Government’s proposals are workable.
“In all the time I’ve been going to Northern Ireland… nobody has ever mentioned this as a problem,” he said.
“So I honesty think with modern technology, modern invoicing, this is all easily surmountable.”