The Taoiseach has called on the parties in Northern Ireland to "seize the opportunity" to be presented to them tomorrow to copperfasten peace.
As he finalised plans to return to the North tomorrow for the publication of the British-Irish document designed to break the political deadlock, Mr Ahern said the joint paper would offer "an unprecedented opportunity to finish the job" begun on Good Friday 1998.
The "acts of completion" now required of all sides would be reflected in tomorrow's document, he said. It would offer no easy options, but the acts demanded of all parties had the capacity to to bring the current political uncertainty to an end.
The Taoiseach was speaking to reporters in the grounds of Hillsborough Castle at the end of his meeting with President Bush and the British Prime Minister Mr Tony Blair. Mr Ahern also held separate meetings with the Sinn Féin and Ulster Unionist Party leaderships as decision time approaches.
He declined to predict success, saying there were still issues of contention with a number of the parties. There was a short list of unresolved issues - "Not many, and not one party, and that is why I have said both Minister Cowen, Minister McDowell and myself will continue our efforts."
There is cautions optimism in Government circles that the IRA will announce its intended acts of completion within days of tomorrow's publication. However, the Taoiseach declined to speculate on the republican response. Asked if "at this eleventh hour" he had any idea what the republican attitude was, he said: "As you know you usually have to get to the 13th hour before you get that clear. I'll tell you next week."
For tomorrow's document to succeed would require further commitment and hard work from all sides including the two governments. "We have done everything in the last six months to try to bring these acts of completion. We have faithfully and dutifully listened to everyone's point of view," he said.
Calling on all to seize the opportunity, he said: "We are moving into a phase where people who supported and voted for the agreement will look to those who politically endorsed it to show that it is still a vibrant initiative.
"Five years ago we all took huge risks in making this agreement, and I believe we now have an unprecedented opportunity to finish the job, to ensure that those who took the risks for peace on Good Friday 1998 are also there to receive its rewards, and to continue our journey of hope and optimism knowing that we enjoy such support and solidarity from such powerful friends as the President of the United States, the administration and the US Congress."
Mr Ahern said President Bush's presence was a very powerful restatement of the commitment of the United States to support efforts to secure the full implementation of the agreement.
Success would mark yet another milestone of encouragement for those around the world who believed democratic dialogue and persuasion were the best route to conflict resolution.