• An 11.5-kilometre rail link from St Stephen's Green to Dublin Airport has been singled out for priority from a wider set of proposals aimed at easing congestion in the capital.

• Last week the Railway Procurement Agency (RPA) presented an estimate of €€4.8bn for the airport line to the Cabinet Subcommittee on Infrastructure

• The Minister for Transport, Seamus Brennan, is expected to bring proposals for the airport line to Cabinet shortly. However, the Department of Transport is understood to be unhappy with the RPA's cost projection per kilometre. The €4.8bn estimate is nine times higher than tunneling in Madrid