The Northern Ireland Assembly will be suspended if the joint Irish/British plan to resolve the impasse over decommissioning and the formation of the executive is not accepted within a fortnight, the Taoiseach has said.
As Ulster Unionists and Sinn Fein left Stormont to consult their members and supporters on the joint blueprint, Mr Ahern said he wanted to see the d'Hondt mechanism setting up the power-sharing executive triggered by July 15th. He ruled out the possibility of a further intensive series of talks before then.
"The parties might seek clarification and we will try to give them that. But if people want to rewrite it or put a different interpretation on it, that won't happen."
Mr Ahern told reporters that the only remaining question now was "whether people want to sell the agreement". There was a "glorious opportunity" which would be agreed to "if people mean what they are telling me".
He would not set a date by which he believed actual decommissioning would begin, saying that was a matter for the head of the International Commission on Decommissioning, Gen John de Chastelain. "He is going to give us reports in September, December and May."
He said the discussions on how decommissioning would take place would begin as soon as the republican movement nominated someone to replace Mr Martin McGuinness as the contact person with the decommissioning body.
Mr Ahern emphasised that the Sinn Fein leadership had a difficult job in persuading republicans to accept the deal. "Nobody should underestimate the really difficult task that Gerry Adams and his colleagues have. It is as difficult as that faced by David Trimble."
Mr Ahern also said Mr Trimble "has worked hard these last 15 months" despite the scepticism of many in his party about the Belfast Agreement.
Last night, some Government sources said the divisions within Mr Trimble's party had made negotiations very difficult.
"When we met their delegation we might as well have been meeting four parties," said one source. "David Trimble can't sit at negotiations and say: `This is my view', and that's a difficulty for him."
Another source spoke of having met two well known Ulster Unionist Party politicians earlier in the week. "They had interesting things to say but I didn't know were they speaking for the UUP, or some of the UUP, or just themselves."
Mr Ahern described yesterday as "a great day for Ireland" after the plan was published after nearly a week of intensive talks failed to get all-party agreement. The parties now had a fortnight to agree to the plan and he would be "very disappointed" if it was rejected. The plan "can give this island a bright future if we can agree it".
"I'm very happy that we have created a very clearly understood process." The plan could led to "a more practical and constructive politics that meets the needs of people". It represented an attempt to deal with what was "by far the greatest humanitarian problem facing both governments".
Speaking to reporters last night after what he called "the most difficult negotiations I have ever been involved in", Mr Ahern said the last week had "involved issues that aroused deep emotions, but there was very little rancour". A lot of that was due to the Prime Minister's cool and calm way of trying to move forward.
Mr Ahern spoke of the "endless, endless bilaterals" he had been involved in. "People talk very tough and hard here."
The talks had been necessary. "Vital principles were being upheld. The full dynamic potential of the agreement will be unblocked if we can move forward and support it."
He said the Government team had come to Castle Buildings to do three things: to ensure the terms of the Belfast Agreement were implemented; to have an inclusive executive established; and to negotiate the decommissioning of all paramilitary arms.
"The question is this: If people want to share power on one side, and if people want to see disarmament on the other side, then they will implement the agreement. If they don't want that, or are ambivalent, then they won't."
He acknowledged that it was a difficult time for the parties to consult their respective constituencies on compromise. This weekend saw the Drumcree standoff; next weekend would see the Twelfth demonstrations.
He said many people within the Ulster Unionist Party were sceptical about all aspects of the Good Friday agreement. "I understand their biggest concern is disarmament and if they want that, this will give it to them."
However referring to reports of more basic unionist objections to compromise, he said: "If some people have a difficulty sharing power, that's a different thing.
"David Trimble doesn't have that problem. He wants devolved power, shared power and decommissioning and we will help him get that."