The State's indigenous supply of natural gas is declining, the Minister of State for Public Enterprise, Mr Joe Jacob, told the House.

Reserves in the Kinsale Head and Ballycotton fields were expected to be depleted in four to six years, depending on the rate of use, he said.

Last year, up to 70 per cent of the State's natural gas requirements were imported through the Scotland-Ireland interconnector.

A departmental report on an economic assessment of the future gas supply options had recommended that the Government "wait and see" the outcome of the exploration of the Corrib gas field off the west coast before deciding on future gas supply infrastructure, said Mr Jacob.

"On the basis of studies carried out by my Department and Bord Gais Eireann on forecasts of final demand for natural gas, it is expected that the capacity in the natural gas network will be sufficient to meet final demand until 2004, although larger than expected increases in demand would reduce this period.

"I understand that the position regarding the development of the Corrib field will be more clear later this year and that the Corrib partners, Enterprise Oil, Statoil and Marathon, will then make a decision on whether to proceed with the commercial development of the field."

Mr Jacob said there were other parties interested in building gas supply pipes - one from Belfast and one from the west coast of Britain - but there was some uncertainty about who would build the additional infrastructure needed to meet the supply requirements of the Irish market.

If one or other of the private developers was not committed to building the necessary infrastructure by the end of the year at the very latest, he would approve the building of a second interconnector by BGE. This would allow time for a new supply infrastructure to be put in place to meet anticipated demand.

Mr Jacob was introducing the Gas (Amendment) Bill, 2000, providing for the enlargement of the functions of BGE to allow it to engage in non-gas related activities. The Labour spokesman on public enterprise, Mr Emmet Stagg, warned that the State was facing an emergency where natural gas would have to be rationed, and where power stations would not be supplied, with the certainty of power cuts next year and the year after, and a further worsening of the situation in 2003.

He urged the Minister for Public Enterprise, Ms O'Rourke, to give the necessary authority to the ESB to proceed with the building of its new gas turbine power station in Ringsend, Dublin.

The request for the authorisation had been on the Minister's desk almost as long as the warning notices about power cuts, he added.

Mr Stagg said the Minister should also authorise the construction of a second interconnector to Scotland to allow Ireland to tap into a sufficiency of natural gas from the North Sea. This could be in place and supplying gas by 2002 if a decision was made even now, he said.