Former Irish prime minister Bertie Ahern has said a referendum on Irish reunification would be dangerous and could lead to fresh trouble in Northern Ireland. The ex-taoiseach, a key partner for the British government during the Good Friday negotiations, was reacting to the EU’s decision in Brussels on Saturday to allow for a united Ireland that absorbed the north to join the EU if the province voted to leave the UK.

On a possible border poll – a key Sinn Féin demand – within Northern Ireland, Ahern said: “If you want trouble again in the north play that game. It’s a dangerous game.”



The three-time election-winning Fianna Fáil leader said the EU’s decision to recognise the 1998 Good Friday agreement, which contains clauses allowing for a future border poll, was not a massive surprise. “The fact that all of Europe reiterates that the Good Friday agreement is an international agreement … I’d be very disappointed if any of them said it wasn’t. No it’s not [a big deal]. It’s a fact of life,” Ahern told the Newstalk radio show in Dublin on Sunday.



Ahern, who was first elected taoiseach in 1997, worked closely with Tony Blair to secure firstly the Good Friday agreement and then the 2006 St Andrews agreement, which led in turn to the power-sharing executive headed by Ian Paisley and Martin McGuinness.



While the EU has recognised Northern Ireland’s right to rejoin the union in the context of a united Ireland, the Good Friday agreement stipulates that constitutional change can come about only via a border poll. In last June’s referendum, 56% of the Northern Irish electorate voted to remain within the EU.



But successive opinion polls in the region have also shown a consistent majority in favour of staying within the UK rather than linking up with the Irish republic.



The Ulster Unionist party said on Sunday that the Good Friday/Belfast agreement underpinned the principle of consent on the region’s constitutional status. UUP assembly member Doug Beattie said: “The Ulster Unionist arty has been clear that the focus should be on ensuring that the United Kingdom, and within that Northern Ireland, gets the best deal possible through the UK government’s negotiations with the EU. It is sad that some are opportunistically using Brexit to try and unpick the union.

“The Belfast agreement put the future of Northern Ireland in the hands of the people of Northern Ireland through the principle of consent. Sinn Féin should reflect on that when they talk about protecting the Belfast agreement. They can try and claim a win, but these guidelines do not change the fact that Northern Ireland will remain a part of the United Kingdom while the majority of our citizens wish that to be the case.”