Tony Blair warned the Northern Ireland peace process could be at risk as he joined fellow former prime minister Sir John Major in Londonderry on Thursday to warn against voting to leave the European Union in this month’s referendum.
Mr Blair said it would be “profoundly foolish to risk those foundations of stability” created by the peace process by voting Leave on June 23.
Referring to those campaigning to pull out of the EU, Mr Blair said: “I say, don’t take a punt on these people. Don’t let them take risks with Northern Ireland’s future. Don’t let them undermine our United Kingdom.”
The two former prime ministers played key roles in the 1990s peace process and their comments raise the stakes in the referendum campaign by warning that a Brexit could see the reintroduction of a “hard border” in Ireland between north and south, reigniting political tensions.
Sir John said if Britain left the EU there was also “a serious risk” it could trigger heightened demands for a second independence referendum in Scotland.
Mr Major told a gathering of students at Magee College: “The unity of the United Kingdom itself is on the ballot paper in two weeks’ time.”
The choreographed intervention - albeit staged in a city which for three decades was one of the centres of a militant campaign by the IRA to break up the UK - is an attempt by the Remain camp to seize back the initiative and shift the EU referendum debate away from immigration.
The Remain camp argues that after a Brexit vote, the border in Ireland would become an external frontier between the EU and the UK, with the possible introduction of frontier controls and customs checks.
The UK and Ireland operate a common travel area allowing free movement between the two countries.
If the UK quits the EU, Remain campaigners say border checks are likely to be needed to prevent EU nationals from third countries such as Poland or Romania entering the UK through a “back door” migration route to mainland Britain.
However Theresa Villiers, the Northern Ireland secretary and a leading Leave campaigner, rejected suggestions there would have to be border checks between the Republic of Ireland and Northern Ireland. She said the common travel area existed for decades before the UK joined the EU and it would continue to exist if the UK voted to leave. She said it had survived a civil war, a world war, and 30 years of the Troubles.
“There is absolutely no reason why it can’t survive a Brexit vote,” she said.
Ms Villiers told the Financial Times that Britain would deal with the issue without the need for border checks by finding and deporting EU nationals who had entered the country through Northern Ireland without having a legal right to work.
But Nigel Lawson, the former Tory chancellor and a Brexit campaigner, said in April: “There would be border controls but not a prevention of genuine Irish coming in.”
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The idea of the north-south border becoming a “hard” frontier would be a step backwards from the progress made since the Good Friday peace agreement in 1998.
The Treasury has also warned that if Britain left the EU and was outside its customs union and common trade policy, the border with Ireland “could be subject to various forms of customs controls and their liability to duty determined according to complex rules of origin”.
The border arrangements in Ireland are unlikely to feature highly in the minds of many British voters on June 23, but Sir John and Mr Blair both warned a Brexit vote could have multiple unintended consequences.
But Nigel Dodds of the Democratic Unionists, the only Northern Ireland party to back Leave, accused the two prime ministers of “irresponsibility” and claimed the peace had “never been more secure”.
The North Belfast MP tweeted: “While irresponsible Blair and Major scaremonger in NI the truth is the political process has never been more secure. Shameful Remain tactic.”
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There is a clear split over how a vote to leave would shape the capital’s future as a financial centre
What the City stands to lose and gain from Brexit
Sectors such as foreign exchange trading have boomed during EU years
What has the EU done for the UK?
The long-running debate over the economic benefits of membership remains unresolved
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