A Yes vote in Friday's referendum on the Belfast Agreement would be a win-win situation for everyone, according to President Bill Clinton.
He urged people in the North to think about what the world would be like in 2010. There would be a much more globalised economy, with Britain and Ireland more involved in the European economy, with the rest of the world and with each other, "meeting at the tip of Northern Ireland, economically and psychologically".
"The people that are at that vortex are going to have a very interesting, very rich, very good life if they vote to live together. If they vote to stay apart they are still going to be frustrated, distrustful, angry and a little bit left out."
Mr Clinton and the British Prime Minister, Mr Blair, who were both in Birmingham for the G8 summit, were being interviewed on BBC1's Breakfast with Frost programme yesterday.
Everyone had hope and fear inside themselves, Mr Clinton said. But he predicted that the clearheadedness of the people would prevail and they would vote for the future.
He added: "We know that democracies of diverse people are interesting places to live when your uniqueness is valued, but you understand that what you have in common as human beings is more important than what divides you. I believe they will accept that."
Mr Clinton stressed the agreement set up a framework to embody "in a thousand ways" the principle of consent. If people did not like some detail, and a majority could be found to agree on it, they would be free to modify it in future within the framework of the agreement: "Why take the risk that this moment won't present itself again for another generation?"
Mr Blair said it would be fundamentally wrong to tell people, as opponents of the deal had done, that a No vote would simply lead to renegotiation.
"I will say to people: of course, we are here and we will try and pick up the pieces as best we can . . . We pick up the pieces when everything goes wrong . . . But we would be in a situation where it wouldn't be the status quo.
"There is quite a lot of hope about, and people feel they're making progress. The one thing I've learned in this whole process is that if it doesn't go forwards it goes backwards. It never stays in the same place."
In another interview for GMTV Mr Blair urged the people of Northern Ireland not to let their revulsion at the release of "callous murderers" stop them backing his peace agreement.
He said he understood the "emotional pull of these things" and why people felt a "sense of revulsion when they see these people".
But he warned: "It is actually misguided to use that as a reason to vote against the agreement. The truth of the matter is that this agreement offers the only chance for a stable framework for the future, and even if there are bits in it that people don't like or find difficult, taken as a whole it really offers the only real chance for the future."
He added: "My point to people is that when they see scenes of the Balcombe Street gang and Michael Stone, all people who are callous murderers being let out of jail on a short release in order to attend particular conferences, this is nothing to do with the agreement. These people are out under provisions agreed by a previous government years and years ago," Mr Blair said.
He said he still had worries about the threat of violence but added: "I think that that is why it is so important to get a resounding Yes vote, so that those undemocratic terrorist groups that carry on are going to carry on in circumstances where they are defying the clearly expressed will of the people."
His comments were made as the G8 heads of the industrialised world gave their backing to the Belfast Agreement, and called for it to be given the widest possible support.
"We pledge our countries' support for this process," they said.
In a statement the leaders said: "We recognise that the agreement must win the support of the people in Northern Ireland and the Republic of Ireland.
"While acknowledging that it presents challenges to all parties, we hope it will achieve the widest possible support, not only as a basis for political stability and peace, but also as an opportunity for economic development and prosperity for all Northern Ireland's people."