The Taoiseach has rounded on "speculation mongers" for talking up prospects of a done deal among the parties in Northern Ireland concerning fresh elections.
Mr Ahern accused some commentators of "running ahead of us", adding that "they don't serve us very well and are totally unhelpful in my view".
He went on to illustrate graphically the difficulties that have to be overcome if elections are to be held and a working executive formed at Stormont. "We want elections and we want to try to achieve a working executive out of those elections," he said.
But, speaking in Dublin, Mr Ahern pointed to the amount of work still to be done. "Everybody knows what is required but there is no package agreed at this stage, or even tentatively agreed."
Sinn Féin president Mr Gerry Adams also condemned as unhelpful what he called "ill-informed speculation of imminent IRA gestures or breakthroughs".
"The reality is that all of the participants in these discussions, including republicans, have crucial contributions to make to any resolution," he said yesterday in Omagh, Co Tyrone.
"The British government has significant matters, on the Human Rights Commission, on equality, on policing and demilitarisation and other issues which it has responsibility for resolving. The Irish Government too has a contribution to make and unionists need to convince nationalists and republicans of their serious intent towards the sustainability of the institutions and the implementation of the outstanding aspects of the Good Friday agreement."
The notes of caution were echoed by a well-placed political source at Stormont.
The Irish Times was told some people had "jumped from optimism to declaring it's all over", and this was far from the case.
Northern Secretary Mr Paul Murphy is understood to agree with Mr Ahern's caution but it is also understood that the political climate is positive and that productive meetings have already been held.
One source suggested that the mood at meetings involving the Sinn Féin president and the Ulster Unionist leader was more positive than during the spring, in the run-up to the postponed Assembly election.
Mr Murphy will be in Northern Ireland early next week when he will hold private individual meetings with political figures, understood to be Mr Adams and Mr David Trimble. The Northern Ireland Office believes that a good relationship between Mr Trimble and Mr Adams contributes to the chances of a political breakthrough.
Mr Trimble's party opponents continue to make warning noises in the background. Mr Jeffrey Donaldson, the Lagan Valley MP who quit the Westminster whip to oppose his leader's stance on the Joint Declaration, spoke yesterday of the need for verification of any future act of paramilitary decommissioning.
Despite the caution from Government Buildings and Stormont, there remains a feeling that sufficient progress is possible to enable an election and the formation of a working executive which could complete the implementation of the Belfast accord.
Politicians continue to scan their diaries for available dates, probably in November. The electoral office is thought to require about six weeks' notice of any poll, making November and early December the most likely time for holding the twice-postponed election.
Although elections are normally held on Thursdays, The Irish Times has been told that this preference is not fixed.