It's his most recent warning on the issue - the former prime minister has warned that Brexit could negatively impact the Northern Ireland peace process."There was always going to be problem when the UK comes out of the single market and customs union of the EU and Republic of Ireland stays in," he told ITV News.
Tony Blair said issues relating to the Irish border were inevitable
"We’ve just got to find a way through it and I hope with the right attitude both from the UK and from Europe, we can".
On Wednesday, talks between Brexit minister Lord Frost and the European Commission’s Maros Sefcovic failed to make a breakthrough on the Northern Ireland protocol - the element of the Brexit deal which has triggered a UK-EU dispute.The EU has threatened to launch a trade war against Britain if it fails to implement checks on goods entering Northern Ireland under the terms of the Brexit “divorce” settlement which Mr Johnson signed. Mr Blair, who played an active role in the historical Northern Ireland peace process, said he's "always been concerned" Brexit could threaten the arrangement.
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He said: "It is, as a matter of principle, an irresolvable problem. If you want an open border between north and south of Ireland, then both have to be in the same relationship to the EU’s single market and customs union.
"Now, with Brexit they’re in different relations and there’s absolutely no way out of that".
Mr Blair advised that officials consider the "most sensible way" of minimising the disruption at the border and minimising differences between Northern Ireland and the rest of Britain.When asked whether EU leaders, like Angela Merkel and Emmanuel Macron, would pressure Boris Johnson to act on the issue, Mr Blair said: "I think the bigger problem will be is they’ll simply say, 'look, you negotiated the protocol and we’re not changing it', so i think it’s more fruitful to look at practical solutions".