The Progressive Democrats' transport spokeswoman, Senator Helen Keogh, has called on Dublin Bus unions not to oppose the company's privatisation.
However, the general secretary of the National Bus and Railworkers' Union, Mr Peter Bunting, insisted the proposals would have to go before the Public Transport Forum provided for in the new national agreement.
Mr Bunting predicted the Government would modify its proposals. "A week is a long time in politics and the three years envisaged for privatisation is aeons. We have seen Government decisions reversed before and this plan is deeply flawed."
Mr Bunting asked: "Who will buy Dublin Bus when the Government says 25 per cent of the routes should be franchised to competitors?"
He also criticised the failure of the Government to propose measures to prevent monopolies developing.
With new agreements looming at Dublin Bus and Bus Eireann, Mr Bunting warned that any attempt at change, other than through a partnership approach, would be strongly resisted.
Speaking at the Progressive Democrats' parliamentary party meeting later yesterday, Senator Keogh said she was "concerned about the very negative views expressed by Mr Bunting".
Bus workers had "nothing to fear and everything to gain from the new proposals".
"Not only is there some protection for existing workers in any privatisation of Dublin Bus that might take place, the new era will lead to enhanced job opportunities because of greater commuter use of bus services," she said.
The proposals were also welcomed by the Competition Council of the Irish Business and Employers Confederation. It said the new Public Transport Regulatory Authority should be set up quickly. However, SIPTU national industrial secretary Mr Noel Dowling said the forum was the only way to approach the problem "in a sensible and structured way".