Northern Secretary of State Peter Hain has been quoted in a US interview as advocating the development of a single all-Ireland economy.
Mr Hain was reported to have told the New York-based Irish Echo: "In future decades, it is going to be increasingly difficult to look at the economy of north and south except as a sort of island of Ireland economy.
"We are deepening north-south co-operation in a number of areas. "The Northern Ireland economy, though it is doing better than ever in its history, is not sustainable in the long-term.
"I don't want the Northern Ireland economy to be a dependent economy as it is now, with a sort of UK, 'big brother' umbrella over it. It needs to be much more self-sufficient, so that's what we're trying to do."
However the remarks were branded disgraceful by DUP Assembly member George Dawson.
Mr Dawson accused the Northern Secretary of jeopardising the North's economy after he was quoted as saying it was not sustainable in the long-run.
"Peter Hain 's comments to the Irish Echoduring his American trip are amongst the most disgraceful ever uttered by a Secretary of State," the East Antrim MLA said.
"His assertion that the Northern Ireland economy is "not sustainable in the longer term" is inaccurate and deeply damaging to the efforts of Invest NI in attracting Foreign Direct Investment.