Former taoiseach Bertie Ahern has said Brexit is the most serious challenge facing Ireland.
Addressing the Seanad Select Committee on Brexit, Mr Ahern said the European Union is a peace process in itself.
He said that "stakeholders that support the EU should do more to re-iterate this important political point to the people of Europe as often as they can”.
Mr Ahern said "we are living in unprecedented times", but this does not mean those involved in the negotiations between the bloc and UK cannot put in place a "framework for the future relationship that Britain is going to have with the EU and vice-versa".
He said the challenges are difficult but not insurmountable.
"Political leadership at the highest level in Europe and a will to succeed are going to have to be cornerstones of these Brexit negotiations if a final agreed solution is going to be secured," he said.
Asked if he would have appointed a Brexit minister, Mr Ahern said: "It would have been eminently sensible. That is my tuppence ha'penny worth. But I think that maybe it has moved on now from that".
He also welcomed the more conciliatory tone in the language used by both sides compared to that in the aftermath of last June’s referendum.
It is easier to dock a ship in calm waters than it is if there is gale force wind blowing over its bow
The former Fianna Fáil leader said Brexit should not be used as a means to towards having a border poll on the future of Northern Ireland.
"The only time in my view, and I will argue this for the rest of my life, we should have a border poll is when the nationalists and republicans, and a respectable sizeable amount of unionists and loyalists are in favour and on the basis of consent.
"Having a sectarian head count or political head count is the last thing we do."
Sinn Féin Senator Niall Ó Donnghaile took issue with Mr Ahern's warning against using Brexit as a means towards having a Border poll, saying: "I do take issue and a wee degree of offence in terms of your language around a democratic exercise on Irish unity. I don't think it would be a sectarian head count."
Mr Ahern said we should see Brexit as an opportunity to "positively change thinks for unionists."
On the issue of Northern Ireland being given special status within the EU, Mr Ahern said the best way for getting special status is by working together, by Stormont working and by the "very active" meetings of the North-South ministerial council.
Concluding his comments to the Seanad committee, Mr Ahern warned: "Jean Claude Juncker President of the European Commission, Michel Barnier, the chief negotiator, and Guy Verhofstadt, they have all said they respect and accept that Ireland suffers, they respect that anything that is in breach of the Good Friday Agreement cannot happen, they understand the past conflict in Ireland and they want to be helpful.
"They have a lot of things to do. It beholds us to put the clear vision of how that becomes a reality. I think that clear vision paper is not done over the next two years, I think it is done over the next two or three months."
Meanwhile, the Taoiseach has said negotiations on Britain's departure from the European Union must not undermine peace in Northern Ireland and there can be no "hard border".
"Whatever happens in the Brexit negotiations, nothing should undermine the peace and stability ... in Northern Ireland, which has taken so long to achieve and in which the European Union has played such an important part," Mr Kenny said at an event in Berlin.
"As demonstrated by recent developments, the peace and stability there remains in a fragile state," he added before meeting German Chancellor Angela Merkel.
"It is therefore critical that there is no return to a hard border," he said.
"This is also about issues of peace and security," Ms Merkel said of Brexit, with a nod to Northern Ireland, and promised "with all due care to help our member state Ireland".
The chancellor said the remaining 27 EU states would take a constructive approach to the Brexit talks and protect their interests, "but we also want to remain good partners".
