The Irish and British governments appear determined to press ahead with an initiative to break the political deadlock in the coming two to three weeks if the current stalemate persists.
The DUP, however, insists that it will not sign up to any agreement that does not conform to its bottom-line demands.
The Taoiseach, Mr Ahern, said in Dublin yesterday that people would be "amused" if they understood what was holding up agreement.
Mr Ahern said it would be an "enormous tragedy" if attempts to restore devolution had to be postponed to 2006 when the governments and the parties were now so close to a deal.
He said the two main issues delaying agreement were ensuring the stability of the Belfast Agreement institutions and IRA disarmament. Reports that the IRA was prepared to fully decommission by the end of December were "very near the mark".
The governments in the absence of agreement in the next two weeks must decide whether to put "take it or leave it proposals" to the parties, or to postpone any further attempts to end the logjam until 2006.
"We are within a fortnight of making a decision to crack the outstanding points and do it successfully and comprehensively, or decide that having almost got there for the third time in a two-year period that we haven't got enough, and then to leave it aside," said Mr Ahern.
A senior British source told The Irish Times last night that the British Prime Minister, Mr Tony Blair, agreed with the Taoiseach that the governments could not indefinitely defer taking action.
In Brussels on Friday Mr Ahern indicated that the governments were set to propose the phased re-establishment of the Northern Executive and Assembly in return for an end to IRA activity and decommissioning. However, such a proposal would appear problematic if the DUP did not endorse or at least acquiesce to the governments' proposals.
Last night a DUP spokesman said issues relating to matters such as ministerial accountability and the timing of the transfer of responsibility for policing and criminal justice to the Assembly were still not resolved.
"When the right deal is there the DUP will have no hesitation in signing up to it. And while there has been considerable progress since the Leeds Castle talks, the right deal is not there yet," said the DUP spokesman.
The DUP position has prompted suspicion among Sinn Féin and SDLP politicians in particular that it has no real intention of finalising agreement until after the next British general election, expected in the spring or early summer.
Mr Ahern suggested such a position would be tactically wrong. "I fear that some people think there's some tactical advantage to be gained by long-fingering thisBut my personal assessment, because I'm so long dealing with this, is they're wrong..."
