There is doubt over whether the Government has made up its mind on what we will do with the south part of the MetroLink project. As we are speaking, the National Transport Authority has outlined its latest paper on the next level of design options. I have had a chance to read it online and we look forward to attending its session this afternoon with Members of Parliament to ask questions. I hope we can agree, as we have agreed on the previous occasion, to bring this before the Oireachtas Joint Committee on Transport, Tourism and Sport for a really detailed debate. We all know the history of this with 20 years of planning the metro. It was always planned to be extended to the Luas green line. Real concerns arise that in a driverless segregated system, the section from Ranelagh to Dundrum, would have the serious consequences of loss of pedestrian, cycling and local accessibility. We had expected some sort of response to that today to see what would be technically possible.

The response seems to be to put it off for 20 years. We will not proceed now. We will run the tunnel machine beyond Charlemont to just south of Ranelagh and use it as a shunting yard while we wait 20 years before upgrading it. That is not the right approach to take. We need to be ambitious in public transport development. What the Taoiseach said earlier about the climate is very true. We need to do many things and so much more. In transport alone, even with the MetroLink and the BusConnects project in Dublin, the National Transport Authority expects a 30% increase in emissions when what we need a 30% decrease by 2030.

The Government needs to be open to looking at all options, including extending the Luas green line now if that is the best transport solution. We should look at other solutions. One of people's main concerns is that the lack of upgrade to the Luas green line will see people from Sandyford, Cherrywood and beyond, where large developments are occurring, not having a sufficient capacity to get on the line.

That is a real issue. One option we could choose to solve that problem would be that rather than stopping the tunnelling machine in Ranelagh, it could continue on to UCD and from there to Sandyford, thus creating a new line that has heightened demands - UCD is a huge centre and there are others along that route – thereby solving that problem. The other might be to run it to the south west to Terenure and Rathfarnham but, critically, we are in a consultation process where we should not shut out the options. The Minister for Transport, Tourism and Sport said last month: "I won't countenance any project which comes up with a proposal which inconveniences commuters" to the extent of a four-year closure, which he stated was possible. He said: "it won't be happening". Is that the last word from the Government on this issue or can we examine all the options in a sensible way to make sure we get a transport solution for south Dublin? We will need the same for west and north Dublin and for every other city and every rural community. We need radical ambitious plans for public transport to stop the €2 billion cost of gridlock that is evolving, to tackle our emissions and to improve our quality of life. Doing nothing or abandoning public transport projects should not be the answer. Is the Taoiseach open to looking at all the options that are still before us?

I thank the Deputy for his question. First, to pick up on a theme mentioned earlier, I do not think we can meet our obligations when it comes to reducing emissions, taking climate action or satisfying the demands of young people who want us to do more around climate change without a metro but just like a carbon tax, a metro on its own does not solve the problem. It only deals with one part of the problem but it needs to be all these things and not any one of them if we are serious about taking climate action.

Like the Deputy, I also represent a commuter constituency. Today thousands of my constituents will spend an hour or more in their cars or on the bus getting in and out of town, which has an enormous impact on people's quality of life, but things can be so much better. In a city of this size we can have people getting into the city centre in 30 or 35 minutes, even from the outer suburbs, but that means investing in public transport and cycling and in projects such as the metro and BusConnects as well as, for example, DART electrification to the western suburbs.

All the solutions are not in Dublin. In order to solve our congestion problems we need to build up the other big cities and some other towns so that we have much more balanced development. All the philosophy behind Project Ireland 2040 is about growing those towns and cities at twice the rate of Dublin. Part of the solution to Dublin's problems is to develop our other cities and we are very committed to that. It involves better planning in Dublin so we that have much more high density, which would make public transport more viable. It also involves investment in cycling and public transport, as the Deputy mentioned.

I had a chance to meet the people in the National Transport Authority a few weeks ago to get a briefing from them as to what the direction of travel was. My understanding is that the new alignment, which the authority is going to produce today, will involve some important changes. It will protect the Na Fianna GAA club, which I am sure all of us will agree is very important. It will also protect Kickhams, which is also very important, in order that the club can move to its new grounds and have new facilities in Ballymun. It will change the proposal to tunnel through Ranelagh, which I believe the residents of Ranelagh will very much welcome. Rather than going the full way down the line, the tunnel will stop in Ranelagh and the Luas south of there, the green line, will be very significantly upgraded. The reason the authority decided not to go the whole way down that line is that it would involve closing the Luas for two to four years, which it had determined, and I agree, was not a viable option.

To answer the Deputy's question, notwithstanding the fact that this is a statutory process, we need to be open to suggestions as to where the tunnel should go from there. The Deputy suggested Terenure and Rathfarnham but they have said to me that the density there would not justify it - we would have to put in a lot more high-rise building around there in order to justify it - but that UCD and Sandyford might make sense. "Yes" is the answer to the Deputy's question. I think we should be open to considering that but I would not like that to hold up the project because nobody is arguing against it in the airport, in Swords, Glasnevin, Santry or at the Mater - that entire area has been waiting for this for far too long. I would not like anything to hold that up.

I fully agree; nothing should hold it up. We should, at real speed, look at those other options. I take some comfort from the Taoiseach saying the Government is willing to do that and that with respect to the comment by the Minister, Deputy Ross, to the effect that he would not countenance that proposal and that it would not be happening, nothing else happening is not the final word.

That area in Rathfarnham and beyond to Knocklyon and Firhouse is very badly served by public transport and as there is large-scale development happening in the area, those people deserve a first class public transport system. The advantage of running to UCD is that we could have a whole series of station stops where development is going to occur anyway. To put the stations in at the same time as the foundations are being poured makes real sense as the numbers would be huge straightaway and it solves the problem of capacity on the green line.

It is a statutory process. We do not want to run the NTA's business. It has to do the proper engineering analysis and this has to be done in the end with best transport engineering. Where is the best place for us to have that civil debate? It is not just obsessing about south Dublin, but south Dublin happens to be the issue before us and is where we will have a tunnelling machine coming across the Liffey. We need to know what to do. Are we best to give our advice to the Joint Committee on Transport, Tourism and Sport or directly to the NTA? How do we engage with the Government so the options suggested here today can be considered in a rational, reasoned and ambitious way?

As I understand it, what the Minister, Deputy Ross, said he cannot countenance is a two-year to four-year closure of the Luas green line. I agree with him. I think that would be unacceptable.

Why was it published in the first place? They all endorsed it a couple of years ago.

Second, I think we should have a discussion about where the tunnel goes. The current proposal, as I understand it, is to leave the machine in the ground somewhere around Ranelagh. We should have that discussion about whether it would make sense to go west or east from there, perhaps to UCD, perhaps to Sandyford. As the Deputy points out, the option of going to Sandyford solves the long-term problem of the Luas green line, so there is common sense in that, in my view.

How do we take it from here? Again, as I understand it, it is a statutory process, the NTA will publish the revised route today and there will be a further statutory consultation period during which people will be able to make further suggestions. An engagement with the Joint Committee on Transport, Tourism and Sport, chaired by Deputy Fergus O'Dowd, would be another good step forward. However, I would say this and I know the Deputy will agree with me: if we are going to examine where the tunnel goes south, let us not allow it to hold up the rest of the project. Nobody doubts the need for it at Swords, the airport, Santry, DCU, the Mater, the north inner city, the intersect with the Maynooth line at Glasnevin and through to O'Connell Street, Trinity and St. Stephen's Green, and linking up with DART and Luas. We need to get this done.