The former prime minister’s comments came one day before crunch talks in Brussels, in which Theresa May needs to make a “final offer” on the Irish border
Brexit jeopardising Northern Ireland peace process, says Blair
The Good Friday peace agreement that ended the conflict in Northern Ireland is “at risk because of Brexit”, Tony Blair has said.
The former British prime minister, who was one of the chief architects of the 1998 deal, told the BBC on Sunday that it was written on the assumption that both Ireland and the UK were EU member states.
Allowing free movement of people, goods and an open border between the Republic of Ireland and Northern Ireland had been critical in reaching an agreement, he said.
But there are fears that Brexit could lead to a hardening of the border on the island of Ireland, similar to the one that existed in the years before the agreement was signed.
"If you end up with a hard border, obviously that causes tensions,” Mr Blair said.
"It doesn't mean that you should abandon the Good Friday Agreement, but it poses real challenges to it."
Mr Blair’s comments come just one day before crunch Brexit talks in Brussels, in which prime minister Theresa May needs to make a “final offer” on the Irish border.
European Council president Donald Tusk has insisted that Monday will mark the "absolute deadline" for London to deliver "sufficient progress" in its divorce offer, before leaders decide whether to move the discussions on to a future trade relationship.
On Friday, Mr Tusk said the bloc will refuse Britain’s demand for talks on a post-Brexit transition and future trade pact if Ireland is not satisfied with London’s offer on border arrangements with Northern Ireland.
Mr Tusk, who will chair a summit of EU leaders on the issue in two weeks, was speaking after meeting the Irish prime minister Leo Varadkar in Dublin.
"Before proposing guidelines on transition and future relations to the leaders, I will consult the taoiseach [Mr Varadkar] if the UK offer is sufficient for the Irish government," Mr Tusk said.
"Let me say very clearly: if the UK offer is unacceptable for Ireland, it will also be unacceptable for the EU," he said.
"This is why the key to the UK’s future lies - in some ways - in Dublin, at least as long as Brexit negotiations continue."
After speaking with Mr Tusk, Mr Varadkar added: "The UK must offer credible, concrete and workable solutions that guarantee that there will be no hard border, whatever the outcome of the negotiations and whatever the future relationship between the EU and the UK is."
"The next couple of days will be crucial," he said.
Speaking to the BBC on Sunday, Simon Coveney, Ireland's tánaiste (deputy prime minister) warned that a hard border must not become the "collateral damage" of Brexit.
"We cannot allow some kind of collateral damage or unintended consequence of Brexit to [be] the recreation of a border on the island of Ireland," he said.
Mr Blair admitted that it was difficult to see how the issue of a hard border could be resolved.
He called on negotiators to try and overcome the “conundrum” of creating a hard border between Britain and the EU after Brexit, while at the same time, avoiding one re-emerging on the island of Ireland.
Mr Blair has previously called for a second nationwide vote to decide whether the UK should leave the EU when the full detail of any negotiated deal is known.
The vote – either a national election or referendum - could lead to a reversal of the decision to leave the EU if the terms struck during the negotiations were unfavourable, the former prime minister told The National in October.
“What’s important is that we don’t have a vote on the divorce until we see the terms of the new relationship,” he said. “It could be an election, it could be a referendum … you have to have a final say.”