Prime Minister Theresa May has repeatedly declared the United Kingdom of Great Britain and Northern Ireland will leave the EU together – with no exceptions.
But now Mr Smith, who failed in a bid to oust Jeremy Corbyn as Labour leader last year, has claimed Northern Ireland could remain in the EU and single market even if England, Wales and Scotland all leave.
The bizarre proposal has already prompted a furious response from Northern Irish unionists, who see such a move as part of a slow-motion unification of the island.
The Democratic Unionist Party (DUP) fear Northern Ireland remaining in the bloc would result in Stormont working closer and closer with the Republic of Ireland’s Dail government rather than Westminster.
Mr Smith made the claim at an event organised by Sinn Fein at the Labour party conference yesterday.
He was part of a panel discussing the future of the border between the Republic of Ireland and the north of the country, which will become the only land border between the EU and the UK after Brexit.
Mr Smith said: “What I am increasingly convinced of myself is we will need to be much more imaginative and much more concrete in what we offer.
“Does it mean Northern Ireland needs to remain within the EU and as part of Britain, and with people being able to identify within Northern Ireland as Irish?
“I think that is the space we need to be in. I do not see another solution that allows for a different outcome.”
When asked for more details Mr Smith admitted he was unsure how to “frame” the proposal, which could also pave the way for pro-Remain Scotland to stay in the bloc.
He said: “There have been various suggestions about the European Economic Area, about Northern Ireland remaining in some form of the single market and customs union, and one of the things that is beholden on the British government is not to rule out any of those imaginative solutions.”
The proposal drew a disdainful response from the DUP, who described it as “stillborn”.
MP Ian Paisley Jr, son of fiery preacher and DUP founder Ian Paisley, said: “This solution was stillborn. Everyone has moved on except Sinn Fein.
“Owen should use his influence to bring them back out of the woods.”
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