Charlie Flanagan talks to Irish News Political Correspondent John Manley. Picture by Hugh Russell

THE fate of the common travel area between Ireland and Britain after a 'Brexit' would not be decided solely by the authorities in London and Dublin, the Republic's minister for foreign affairs has warned.

Charlie Flanagan said there may be issues around the movement of goods and people that would have to be determined collectively by the European Union's 27 remaining members.

Speaking to The Irish News during his first visit north since being reappointed as the foreign affairs post, the Laois–Offaly Fine Gael TD said while next month's referendum was a "matter exclusively for the people of Northern Ireland and Britain", he was keen to stress the importance of the EU on both sides of the border.

Mr Flanagan cautioned against saying the peace process would break down if the UK left Europe, but said the EU's contribution to nurturing peace in the north could not be overestimated.

The minister said Europe had always been a "constructive arena" for helping secure peace and stability between Ireland and Britain, and Brussels had shown a "huge font" of political goodwill existed towards Ireland as a whole.

"I don't wish to exaggerate it nor do I wish to make wild claims, but I do acknowledge that history has indeed recorded the facts – there were times when there were issues in Northern Ireland, between parties and between communities, where the arena the EU provided created an opportunity for reaching a settlement on certain issues," he said.

Mr Flanagan said that in the weeks running up to the June 23 referendum he would be stressing the importance of British-Irish relations and north-south relations.

"I believe strongly and clearly that the UK should remain an active and constructive member of the European Union and I believe it's important that a campaign of information and a vigorous debate of the issues takes place here in Northern Ireland," he said.

"I'm also anxious that Dublin's strategic interest be known in that regard."

The minister accepted that his views are at variance with those of the pro-Brexit Secretary of State Theresa Villiers but insisted it would not affect their "most constructive relationship".

Mr Flanagan's remarks on the continued existence of the common travel area in the event of a 'Leave' victory contradict those of Ms Villiers, who has insisted that movement across the Irish border need not be restricted.

He said "contingency plans" are in place and that the Dublin government has considered "the likely (post-Brexit) scenario" but nobody could say "with any certainty" that the common travel area would prevail.

"Should there be a change in status and should the United Kingdom leave the European Union it would obviously result in a new scenario – we'd be looking at an EU external border – and I don't think these are issues that can be resolved entirely by the UK and Ireland," he said.

"Ultimately, there may be issues that would be decided by the 27 EU member states, so at best this will give rise to a great degree of uncertainty. I don't believe it's therefore possible for people to say with any degree of certainty that the situation will remain the same – I don't believe it can."

Mr Flanagan said a UK vote to leaver the EU would result in an "enormous challenge of an unprecedented nature".