The impending Cabinet reshuffle may delay agreement on a deal between unions and the Department of Transport on the future of Dublin Bus.
Union sources have indicated that it may not be possible to achieve a deal by this Friday because of uncertainty over whether the Minister for Transport, Mr Brennan is to continue in his current role after September 29th, when the reshuffle will be complete.
However, a spokeswomen for the Department denied that the talks were being undermined by the reshuffle and said officials attending the discussions were looking to reach an agreement.
The current round of talks started at the Labour Relations Commission (LRC) this morning.
The Friday deadline was set by the chairman of the LRC, Mr Kevin Foley. But if a deal is not agreed by this date the talks are expected to continue into next week.
Mr Foley has said it should be possible to agree a deal which ensures Dublin Bus remains viable while achieving a genuine market opening.
When Mr Brennan announced his plan to break up CIE in 2002, private operators were to be given access to 25 per cent of Dublin Bus's routes to increase competition.
This was opposed by Siptu and the National Bus and Rail Union (NBRU). The unions ran a no fares day in July last year and also held a number of transport stoppages. A series of strikes planned for this July were called after both sides agreed to attend the current talks.
The unions are seeking to protect the terms and conditions of employment of Dublin Bus staff and ensure that the semi-state company is neither diminished in size nor barred from competing for new routes.