Public transport users face a series of national strikes this summer, beginning with a one-day stoppage on July 20th.
Members of the National Bus and Rail Union voted by a nine-to-one majority to take industrial action in their ongoing row with the Minister for Transport, Mr Brennan, over the future of CIÉ. A spokesman for the Minister said he could see no reason for the action contemplated.
The other main union in CIÉ, SIPTU, has not balloted for industrial action. Members would be likely to support any strike by the NBRU, however, so a shutdown of Dublin Bus, Iarnród Éireann and Bus Éireann services could be expected.
The NBRU strike later this month is to be followed by a further one-day stoppage on August 4th and a two-day stoppage on August 24th and 25th.
A three-day strike is to begin on Tuesday, September 7th, after which the NBRU said it would review the situation.
The decision to strike is over what the union claims is a failure of the Department of Transport to provide definitive proposals on the future of Dublin Bus by an agreed deadline.
It said June 8th, the last time the sides met, was the third occasion that the Department had failed to meet a deadline to provide documents.
In the meantime, the union says, the Department has continued to issue licences to private companies operating in Dublin.
"The manner in which licences are being issued does nothing for competition or improving services to the public," said the union's general secretary, Mr Liam Tobin.
"Instead the system allows private operators to negotiate in secret with the Department on how best to 'cherry pick' routes and schedules for ridiculously low fees."
Mr Brennan's spokesman, however, said just eight new licences had been issued to private operators in Dublin over the past 18 months. "The level of competition involved is minuscule given the size of the market."
Mr Brennan could not see the justification for the action threatened, given that there had been 15 meetings with the unions this year and talks were making progress, the spokesman said.
The unions, he added, had sought statutory provisions setting out minimum pay and conditions in the public transport industry.
The Department had explained, at the meeting on June 8th, that this proposal had potentially far-reaching implications. Further discussions would have to take place with other departments and members of the Cabinet.