Dublin Port Tunnel is a "huge white elephant" because it is operating at only a fraction of its capacity and no buses are using it, the Dáil has been told.
Fine Gael transport spokeswoman Olivia Mitchell said "encouraging the use of the tunnel by public and private transport operators should be an absolute priority".
During transport questions the Dublin South TD said "I laughed when I heard about it being used by one million vehicles in the past six months. That figure represents only a fraction of its capacity."
The port tunnel, like the M50 currently, had two lanes and a similar capacity. The tunnel carried about 5,000 vehicles a day compared to an estimated 120,000 on the M50.
"The current nonsensical position is a direct result of failure to make any progress on the reform of the 1932 Act," she said, and called on Minister for Transport Noel Dempsey to make the issue a priority.
Mr Dempsey stressed, however, that "my absolute priority is to ensure that the DTA [Dublin Transport Authority] legislation is published, and that the authority will be established as quickly as possible.
"Immediately thereafter, I intend to reform the bus market and the Transport Acts 1932 and 1958.
"In my 10 or 12 years of experience as a Minister I have learned that one cannot have 25 priorities, because none of them would ever be dealt with properly."
Mr Dempsey said it was not now possible to give a precise timing for the publication of legislation on the reform of the bus market. However the licensing provisions of existing legislation "will continue to be applied, and all applications and notifications from bus operators will be considered on their merits in accordance with the provisions of the legislation".
