Industrial action on buses and trains could go ahead within two weeks as part of union opposition to plans by the Minister for Transport, Mr Brennan, to break up CIE and privatise routes.
In a statement today the National Bus and Railworkers' Union (NBRU) said its national executive will meet on Tuesday to discuss the progression of Mr Brennan's plans "while talks are still in progress between his officials and the CIE unions".
The union said it expects to reinstate its campaign of action deferred last summer at the request of the department.
Mr Liam Tobin, NBRU general secretary today accused Mr Brennan of a "shameless act of treachery" in proceeding with the talks while also progressing his plans to break-up the company.
"I think at this stage the talks' process has lost all credibility and integrity and we will be looking at the reinstitution of the Campaign of Action, which began with the 'No Fares Day' last July."