Northern Ireland could be given joint EU and UK status and a "buffer zone" on its border with the Republic, under new plans being drawn up by David Davis, according to reports.
There was no immediate response from Mr Davis's Department for Exiting the EU to a report in The Sun suggesting the Brexit Secretary is to put forward a radical new solution to the thorny issue of future customs arrangements.
Theresa May's Brexit war cabinet is split down the middle between the Prime Minister's preferred "customs partnership", under which the UK would gather tariffs on behalf of the EU, and the so-called "maximum facilitation" solution using technology to avoid the need for border checks.
With pressure mounting to agree a position before a summit of EU leaders on June 28, Mrs May set up two working groups to find amendments to the two schemes which could unite her feuding ministers.
According to The Sun, Mr Davis - who heads the Max Fac group - is ready to drop his support for technological solutions, after police warned that infrastructure like numberplate recognition cameras would become a target for sectarian attack.
Instead, he is reportedly drawing up a new plan based on the "double-hatted" model in place in Liechtenstein, which would allow the province to operate both UK and EU regulations at the same time.
A 10-mile wide "special economic zone" would be created along the 310-mile border, within which local traders could operate under the Republic's trade rules.
An unnamed Whitehall source told the paper: "Max Fac 2 is tremendously complicated, but it's at least something the Cabinet can unite around."
Liechtenstein is not in the EU, and sits between Switzerland and Austria. Image: Google Maps
The source acknowledged it would be a challenge to secure backing for the plan from the Democratic Unionist Party, which props up Mrs May's Government at Westminster and has made clear that it does not want Northern Ireland treated differently from the rest of the UK.
Talking to talkRADIO Andrew Woodcock, political editor at Press Association said: “The latest increasingly fantastical solution on how to keep the Irish border open - according to the Sun, David Davis has a new plan that NI would become like Liechtenstein.
“NI would simultaneously operate both British and EU tariffs and there’d be a 10 mile buffer zone around the border which local traders would be able to cross without any sort of hindrance as long as they keep within this buffer zone.
“This meant to avoid the need for cameras and checks. He’s hoping this will be the breakthrough, they’ve been stuck in a stalemate as to how to get a solution that’ll satisfy Britain and the European Commission, but also satisfy the DUP, who are propping Theresa May’s government in Westminster.”
What is the deal with Liechtenstein?
The microstate is located in-between Switzerland and Austria, and while it’s not a member of the European Union, it participates in the European Economic Area and the Schengen Area.
What this means is: the state is able to access the single market, and allow the free movement of goods from around the EU, but at the same time it’s allowed to maintain its custom union deals with Switzerland who are also not in the European Union.
Liechtenstein is free to make their own laws, but must abide by EU regulations if it affects the European Economic Area.
As Liechtenstein is fully integrated into the Swiss economy, and also shares the same currency, it relies heavily on the state for economic growth. If the UK employs this same scenario, it would mean Northern Ireland would still have access to the single market, but also be fully reliant on the UK economy as a whole.
It would help create a much softer border with the Republic of Ireland, and still allow the free movement of goods and people.