TransportPreference should be given to completing the major elements of the upgrading of the national primary road system, according to the ESRI evaluation of the investment priorities for the National Development Plan.

However, it recommends that the current road tolling plans should be seen as preparation for the eventual introduction of a countrywide pay-as-you-drive charges.

This would permit the abolition of vehicle registration tax and annual vehicle licensing fees.

While the institute recommends a substantial increase in investment in public transport, it said plans for main-line rail investment require some re-evaluation.

It recommends that, in the evaluation of all fixed-line public transport investments, a bus-based alternative be included as a matter of routine in the range of options considered.

"Bus-based alternatives are available in all cases, and will often offer higher frequency than train-based schemes for the same overall volume, better ability to penetrate target markets, as well as lower capital and operating costs."

If investment in public transport is to prove economic, it will require co-ordinated changes in the planning guidelines so that cities, particularly Dublin, evolve in a way to make maximum use of this infrastructure.

Any moves towards the consolidation of the commercial seaport sector in Ireland should be subject to review by the competition authorities, while it recommends that any pressures which may emerge for new regional airports should be resisted.

With transport forming a big part of the NDP, it is essential that all plans are firmly based on a proper cost-benefit analysis and it recommends that a single centralised unit in the Department of Finance should undertake this analysis, the ESRI advises.