Mr Albert Reynolds went alone to visit loyalist paramilitary commanders on the Shankill Road in Belfast and knew they would call a ceasefire weeks before their cessation was announced by Mr Gusty Spence.
The former Taoiseach claimed last night that he possessed the wording of their ceasefire announcement in August 1994 before the IRA called its cessation at the end of that month.
In an interview with UTV, Mr Reynolds also said he met members of the Combined Loyalist Military Command at a Dublin hotel for talks.
His Shankill Road visit was, he said, to return the compliment. Mr Reynolds spoke of his admiration for Mr Spence, who, he said, was one of the most honourable men he had ever met.
"I had a copy of the statement to be used by the republican movement on the day they called their ceasefire. But I had prior agreement with the Combined Loyalist Military Command for a complete loyalist ceasefire," he told political correspondent Ken Reid.
He revealed their decision would not come into effect until at least six weeks after the IRA announcement.
Mr Reynolds said he was advised that contact with loyalist paramilitary leaders was "a waste of time".
But he added: "I spoke to them on the phone and they came to Dublin and I went to the Shankill Road. Between all of us, we worked it out."
The former Taoiseach said he had agreed to meet Mr Spence before he held talks with Mr Gerry Adams and Mr Martin McGuinness.
"They decided to come down to Dublin to meet me at the Berkeley Court hotel.
"They would drive into the basement, take the lift up non-stop, be there for as long as they liked," he said.
"But of course I had to arrange that I went there on my own. I was there on my own and I returned the compliment ... when I went to Belfast to see Gusty and David Ervine."
Mr Reynolds also said paragraph five of the declaration, offering assurances to unionists that the Irish State would address anything which threatened their way of life, was crafted during the Shankill Road meeting.
The Combined Loyalist Military Command has since broken up and the UDA ceasefire has been declared bogus by the British government.
Loyalist paramilitaries are held to be responsible for ongoing paramilitary activity, organised crime and racist attacks against ethnic minorities, especially in Belfast.