The National Implementation Body (NIB) tonight requested Labour Court involvement in the long-running bid to end the dispute in the postal services.
The NIB said during intensive talks with both An Post management and the Communications Workers Union it had become aware of significant differences of understanding.
The body said opinion on both sides had differed over the cost and implications of a number of amendments proposed by the union in August to changes in the collection and delivery sector which had been recommended by the court.
A statement from the body said: "The NIB requests the Court to assist the parties in reaching an agreed solution over the period immediately ahead, ending on Tuesday, 22nd November, 2005. The NIB has agreed to brief the Court on the detail of its discussions with the parties over recent weeks."
The CWU suspended industrial action by its members last week, after its national overtime ban and strike at the GPO in Dublin lasted just 18 hours.
The union has been seeking changes in four areas of a Labour Court recommendation on major work practice changes sought by An Post in its collection and delivery service.
NIB said the clarification of the cost and implications of the amendments was essential if a basis for a resolution was to be found.
It commissioned accountants Grant Thornton to carry out an analysis of the costs. The trouble-shooter said it was requesting the involvement of the court in light of several matters including problems on both sides and the fact every part of the industrial relations machinery of the State was used extensively to date.
The body said the request was being made to the court in the expectation that any findings would be put by the CWU to workers.