The Taoiseach and the British Prime Minister, Mr Blair, last night failed to resolve their differences over the suspension of the executive and other institutions of the Belfast Agreement, or to agree the next steps to revive the political process in Northern Ireland.
While Mr Blair said he did not want to see the suspension to last any longer than necessary, Mr Ahern made it clear he believed "the operation of the institutions and disposal of arms under the mandate of the international commission should both proceed".
Mr Blair and Mr Ahern were unable to announce the terms of the review envisaged on Monday by the Northern Ireland Secretary, Mr Peter Mandelson, after Mr Gerry Adams, the Sinn Fein president, declared there was no basis for one. Nor were government sources immediately able to indicate how discussions would be advanced in "non-review" mode.
As acrimony filled the Downing Street air, Mr David Trimble, the Ulster Unionist leader, said that as far as he was concerned "this is a review whether you call it that or not".
Clearly battling to put the best gloss on a bad situation, Mr Blair told reporters: "Today wasn't the day we were going to do anything other than discuss what the parameters of the problem were and how we could resolve it. It was a day that was very necessary in allowing us to discuss it between ourselves, and also make sure that all the parties were committed and recommitted themselves to making sure this agreement works. They have done so."
The Taoiseach confined himself to saying that he and Mr Blair "are convinced that there is no reasonable alternative to the full implementation of the Good Friday agreement".
And in a clear reference to the Patten report and upcoming reforms on criminal justice and the equality agenda, Mr Ahern pledged: "Pending the re-establishment of the institutions, we will continue to implement resolutely all the outstanding elements of it [the agreement] within our responsibility."
However, in a barely coded statement after their series of meetings with Sinn Fein, the Ulster Unionists and the SDLP, the Taoiseach made it plain he believed decommissioning would only be achieved if the institutions of government are restored.
Mr Ahern quoted the original assessment of the international commission last November at the end of the Mitchell review, which said "while decommissioning is an essential element of the agreement, the context in which it can be achieved is the overall implementation of that agreement". The assessment also said "all participants have a collective responsibility in this regard".
In line with both those principles, said Mr Ahern, and the need for the full implementation of the agreement, "I believe that the operation of the institutions and disposal of arms under the mandate of the international commission should proceed".
A British source dismissed suggestions of open disagreement between the two governments as "a misreading" of the situation.
However, the show of solidarity and mutual commitment to the agreement came against the backdrop of a stark warning from Mr Adams that Northern Ireland was facing into a dangerous political vacuum. "We cannot make progress in a political vacuum," declared Mr Adams. "We have no room at all to do anything in this situation given the failure of our initiative last weekend. The British establishment seems to think that Sinn Fein can just absorb all of these blows. We cannot. I can only work within the possibilities of human and political endeavour. It is a two-way street."
Mr Trimble said: "The onus is fairly and squarely on the republican movement to themselves put forward proposals as to how this is going to work. The ball is still firmly in their court."