The indications from the Minister for Transport, Mr Brennan, that the height of the Port Tunnel will not be changed from its current useable limit of 4.65 metres casts another shadow over the future use of so-called 'supercube' trucks.
It follows comments by Dr Jim McDaid, Minister of State for Transport, earlier this week in which he proposed an outright ban on such trucks, describing them as potentially dangerous.
The president of the Irish Road Haulage Association (IRHA), Mr Eamonn Morrissey, has described Dr McDaid's comments as "scaremongering".
"Introducing a height restriction under the guise of safety concerns is a bit rich coming from a Government Department that still allows tractors to work on our national roads, not to mention the complete failure of its road safety strategy," he said.
The standard height for truck trailers sold in Ireland is 3.85 metres. Supercube trucks generally begin at about 4.8 metres and can reach up to 4.95 metres. Estimates by the IRHA put the use of these trucks at about five per cent of the entire British and Irish truck fleet. In continental Europe, an unofficial pan-European standard maximum size of 4.1 metres is used due to the size of tunnels on the continent such as the Alpine tunnel, according to the IRHA's director of communication, Mr Jimmy Quinn.
However, he said, due to the principles of subsidiarity within the EU, countries can set their own standards in this area.
"We've always been locked into the British system. Neither here nor in Britain has there been an issue with tunnels. Even when they have built tunnels in Britain, like the Dartford Tunnel outside London, it's got a useable height of 5.1 metres."
As to whether the advent of the Port Tunnel will bring an end to trucks in the city centre, Mr Quinn reckoned that while the quays might be free of trucks, there would still be a need for shops and businesses in the area to be serviced with delivery trucks, not to mention the 30 to 40 trucks that visit the fruit market on the northside of the quays on a daily basis.
"People should also remember that wherever you see a crane, you're going to see trucks delivering everything from metal girders to cement. Then there's the million or so people in the city who go through a lot of milk and cornflakes during the week."