All energies must now focus on breaking through the "Catch 22" situation of decommissioning that continued to bedevil the peace process, according to the Taoiseach.
Shortly after his return to Dublin from the Middle East last night, Mr Ahern said: "There is no obvious way to unlock this dilemma."
He was quoted yesterday as saying in Jerusalem that he would, at all costs, have to prevent a situation where "all hell will break loose". This crisis would arise where the First Minister, Mr David Trimble, attempted to set up the executive without Sinn Fein but failed to get it through the Assembly.
The Taoiseach said he had tried to explain the difficulties to journalists who believed the executive would automatically have Sinn Fein on board.
Last night, he said the dilemma remained that Mr Trimble would not set up the executive until the IRA had begun decommissioning and the IRA would not comply.
Mr Ahern said he would embark right away on a round of meetings and discussions with as many involved parties as possible in an attempt to find a breakthrough.
Mr Ahern said: "I have been saying all along we have to try to formulate some understanding with everybody that we can move this on by setting up the executive and, in some way, to make sure that what is written about decommissioning in the agreement commences."
Asked if he intended to try to persuade Mr Trimble to sit with Sinn Fein in the executive before IRA decommissioning, Mr Ahern said: "It is not going to happen."