The Democratic Unionist Party was last night grappling with whether it could trust the word of the IRA after the Taoiseach and the British Prime Minister conveyed to the party what the paramilitary group might say to try to signal its war was effectively over.
Mr Ahern and Mr Tony Blair held several meetings with the DUP yesterday in which they outlined the nature of the statement the IRA might issue were the DUP to agree to a comprehensive deal.
It is understood the British and Irish leaders were made aware of what was potentially available from the IRA, based on contacts between their officials and republicans earlier this week and last week, and based on their contacts with Sinn Féin leaders at Leeds Castle.
This marked a significant development in the talks as it was the first tangible indication that the IRA was prepared to engage in radical measures to assist the restoration of the Northern executive and Assembly.
Nothing was put down on paper but the two leaders verbally sketched out for the DUP what form an official IRA statement about its future peaceful intentions might take, sources said.
British, Irish and party sources last night said it was "just too close to call" whether in the short time available a deal could be concluded.
Both leaders are insisting that a deal should be done today.
In language similar to that used by her Downing Street opposite number 24 hours before, the Taoiseach's spokeswoman insisted today's 7.30 a.m. start would mark "the final contribution" by Mr Ahern and Mr Blair to this particular negotiation. "These things have to have a beginning and an end," the spokeswoman said. "They [Mr Ahern and Mr Blair] are giving it their all and we should know [on Saturday]."
The talks continued late last night and were resuming at 7.30 this morning. They are due to conclude at lunchtime as Leeds Castle is booked for a wedding.
However, a leading member of the Sinn Féin delegation dismissed the attempt by Mr Blair and Mr Ahern to impose a deadline as "nonsense."
Mr Pat Doherty MP said: "As for this nonsense that politics will come to an end on Saturday afternoon, that is what it is - nonsense."
The Taoiseach's spokeswoman indicated that she did not know "what the alternative" way forward might be, and that any consideration of a "Plan B" would be for after the Leeds Castle negotiation.
The DUP deputy leader, Mr Peter Robinson, in an interview with Downtown Radio, confirmed that the Taoiseach and Prime Minister had briefed him on a potential IRA statement, while also making clear that the DUP would not deviate from its bottom line that it would not share power with Sinn Féin unless the IRA disarmed and ended activity.
"We hear from the governments what they believe the position of republicans to be," he said, while stressing the DUP had to be absolutely convinced of the strength and validity of any IRA statement before it would reciprocate.
"We obviously have to make an assessment of whether [the potential for an IRA statement] is being oversold to us, whether there is an accurate assessment, and ultimately our decisions will have to be taken when we see it in cold print, \ we see the actual text in front of us," added Mr Robinson.
There was a feeling, however, on the governments' side that a persuasive IRA statement that it was effectively going out of business could trigger speedy progress on issues such as power-sharing, ministerial accountability, and even policing.
Mr Robinson, said his party would not be "gulled" into accepting the governments' interpretation of what the IRA might do and say based on a "hint, and a wink and a nod".