The alternative is to use the public private partnership – PPP – as the best way of delivering a Dublin metro system. Such an approach would transfer the bulk of the financial risk to the private sector, bring in substantial private funding and give the private sector a real incentive to complete the project as quickly and efficiently as possible. It would only make sense, however, if it enabled us to deliver the same project at a lower cost to the Exchequer than a conventional contract. The Exchequer's contribution to a metro system delivered by way of PPP should be no more than a fraction of the figures put forward by the RPA. As I stated, the costings put forward by it are not realistic and would impose a huge burden on the taxpayer for years to come.