Northern Ireland parties still divided over border solution post-Brexit
UUP leader Robin Swann has said the reported potential Brexit deal between London and Dublin was "wholly unacceptable" and would have "fundamentally altered the relationship between Northern Ireland and Britain".
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He said the leaked draft text "would present serious challenges to the economic, constitutional and political integrity" of the UK.
"It would undermine the Belfast Agreement, breach the principle of consent and fundamentally alter the relationship between Northern Ireland and Great Britain.
"No amount of 'constructive ambiguity' would cover that up. The Belfast Agreement was not constructed in Brussels," he said.
"Anything that weakens our regulatory regime or means that regulations applicable in Northern Ireland could be set in Dublin or Brussels without consultation, rather than being established in Belfast or Westminster, would be wholly unacceptable."
Mr Swann (right) said Northern Ireland "would be left voiceless" with no say in the design or implementation of the regulations. "It would also mean that if the UK Government is negotiating future trade deals across the world, we would be seen as a place apart. Northern Ireland's constitutional position should not be used as a bargaining chip.
"Whilst we are concerned at initial reports, we will reserve judgement until we have seen the final draft at which point we will deliver a considered response," he added.
But Sinn Fein MEP Martina Anderson repeated her party's call for special status for Northern Ireland.
"This means the North remaining in the customs union and the single market. That would provide the best protection for the Good Friday Agreement and the rights of citizens," she said.
"We cannot have a situation where a minority are allowed to trample over the rights of the majority in the north who voted to remain in the EU."
TUV leader Jim Allister described what was on offer as "a bad deal" which would have been "destructive of the integrity of the UK". "The suggestion of 'regulatory alignment' for part of the UK with the EU single market and customs union would have delivered a border at the Irish Sea. Such is a defining issue for the constitutional integrity of the UK and, therefore, could never be acceptable.
"It would also destroy our primary economic links and prosperity in circumstances where 87% of Northern Ireland sales are within the UK. Thus, anyone with the interests of Northern Ireland at heart could not do other than take a firm stand against such betrayal," he said.
Mr Allister said yesterday's events should not be used as "an excuse" for the whole of the UK to stay in the single market or customs union.
"Such would defeat the purpose and effect of Brexit, which the people of the UK voted for and must obtain as a single and undivided nation," he added.
SDLP leader Colum Eastwood called on the DUP to act "in the best interests of people on these islands".
He said: "The DUP now must move to act in Northern Ireland's interest, not simply serve their own interests.
"For months, the SDLP has been making the case that the only way to avoid a hard border and a hard Brexit on the island of Ireland is to maintain membership of the single market and the customs union. However you want to label it, the end result must be the same."
He added: "The Brexit negotiations must be driven by the best interests of people on these islands, not by narrow isolationist ideology.
"All steps must be taken to protect the North's economy, our political progress and the terms of the Good Friday Agreement. That has long been the position of the European Union. It is welcome that the British Government now seems to be accepting that position."
Alliance deputy leader Stephen Farry welcomed reports that the British Government had been prepared to accept Northern Ireland remaining in the customs union and single market.
Dr Farry said it would be consistent with the UK's current constitutional position and would also "provide a major economic opportunity to be a bridge to different markets".