The Minister for Transport, Mr Brennan, has admitted that aspects of the LUAS Dublin light railway network were a serious mistake and are now a "mess".
Speaking on RTÉ's
Prime Time
last night, the Minister said if he had the chance to begin again on construction of the railway - which is millions of euro over budget and a year behind schedule - he would build it underground.
"If we were starting with a clean sheet of paper, knowing today's figures, you would probably opt for a complete city-wide metro, and you would probably do 100 per cent of it underground," he told the programme.
He also conceded that the proposed routing of the line through the middle of the Red Cow roundabout in West Dublin - one of the country's busiest junctions - was "a huge mistake".
Mr Brennan said his preferred solution was to raise the line on stilts above the roundabout, adding that an announcement on the issue would come soon.