Allen told the Sunday Tribune that although the agency did not have a government mandate to build regional Luas lines, it had provided advice for some such proposals suggested by local authorities and developers.

"We're delighted to be of assistance to people who are considering it. What I say to people is you'd be foolish not to avail of the experience that exists here in Ireland, " he said.

Allen stressed, however, that the RPA was not in the business of promoting light rail schemes that lacked a government mandate.

"It is for Cork, for example, to speak to the government, and we deliver the lines the government mandates us to deliver."

He said some of the proposals brought to the RPA regarding regional Luas lines underestimated the complexity of the engineering involved in building a tram line.

"One of the things we do say when people approach us is that building a Luas line is a complex task. Now that we're at the end of the first two lines [in Dublin], it has proven to be highly successful and we can endorse it but there's a temptation to underestimate the complexity of it."

Allen said, however, that in his opinion, Luas lines could operate successfully in cities such as Cork and Galway.

"Some of the more successful light rail schemes in Europe are in cities like Grenoble, Strasbourg, Montpelier . . .

smaller cities . . . and I think, personally, there could be scope for that in Irish regional cities as well."