The public purse in Northern Ireland could receive a multimillion pound boost from Viridian, which has agreed to the appointment of an expert to value former assets for the purposes of clawback.

Under terms of the privatisation of Northern Ireland Electricity, the British government is entitled to claim a clawback of the profit from the disposal of any former asset.

Viridian and the Department of Enterprise in the North have agreed on the appointment of an independent third party that will re-evaluate any assets which have been sold by the group since NIE's privatisation.

The privatisation of the electricity utility in the North is still a matter of some debate. Mr Douglas McIldoon, the industry regulator in Northern Ireland, believes the current high cost of electricity is a direct result of the way the utility was privatised.

NIE was privatised in two stages. First its four generating stations were sold to three private companies in 1992 at trade sales. One year later, the remainder of NIE was floated on the London Stock Exchange.

The proceeds from the privatisation totalled £774 million sterling (€1,257 million), £356 million of which came from the sale of the power stations, while £418 million was derived from the flotation.

However, the Northern Ireland Audit Office has repeatedly commented on the privatisation, having said previously that it believes the valuation of the power stations may have underestimated their worth.

It has also cast some doubt on how much of the pension fund surplus of the former NIE, which the British Government Actuary estimated at some £23 million, was reflected in the sale proceeds of the generating stations.

The Audit Office believes the sum obtained fell significantly short of that estimate. In subsequent reports, the Audit Office has also drawn attention to the performance of NIE plc's shares following its flotation. The Audit Office has said it was surprised at the wide disparity between the predicted and actual trading yields of NIE plc, and has suggested that it could have been floated at a lower yield with a consequent increase in proceeds.

The latest report from the comptroller and auditor general of the Northern Ireland Audit Office, published in December, once again raises the issue of the privatisation of NIE. The report draws attention to the question of a clawback from the sale of former NIE assets.

According to the Department of Enterprise, this issue could be resolved as early as March following the appointment of an independent expert to value former assets.