The National Pensions Reserve Fund is in negotiation with the European Investment Bank about jointly funding Irish infrastructure projects.

The arrangement would involve some money from the pension fund being loaned alongside EIB money to fund major infrastructure projects.

The arrangement could provide a means for the pension fund to get involved in infrastructure funding, according to Dr Michael Somers, chief executive of the National Treasury Management Agency. The fund could "piggyback" on the EIB's project lending and financing expertise, he said, provided it could find projects which would provide an adequate return. He was speaking after addressing a conference on public private partnerships in Dublin organised by Public Affairs Ireland.

The Government has faced political criticism for investing in the pension fund at a time when there is still a need to invest in infrastructure and a report due shortly on the National Development Plan has recommended an examination of all sources of finance for investment.

The pension fund, with assets of €9 billion, had made clear it was prepared to invest in infrastructure projects, he said. But no approach received so far was sufficiently attractive.

Financing the NDP investment plan is now the subject of debate. This will intensify on the publication of a review of the plan conducted for the Department of Transport. The report has recommended that Government look at alternatives funding sources to pay for the national roads element of the NDP, the price of which has spiralled from €6.8 billion to €16 billion

The consultants have urged Government to consider an "enhanced programme of tolling" as part of the final roll-out of road construction under the NDP.

A confidential review of the first three years of the plan submitted to the Department of Transport by economic consultants Indecon has concluded that additional tolling may be warranted in light of the rising cost of the road plan.