Ministers in Northern Ireland have been unable to reach a decision on public funding for a new gas pipeline that will link Belfast with Derry because the capital costs of the project have not yet been established, industry sources have said.

Final details about the proposed cost of the project and the route the pipeline will follow have yet to be submitted by the joint developers, Bord Gais and the US group, Questar, to the Department of Enterprise, Trade and Investment.

Until these details are submitted the Department of Enterprise, Trade and Investment cannot begin the decision-making process about public funding for the new gas supply pipeline.

It is understood that the department is in daily contact with the joint developers and is confident that it will have resolved all outstanding issues relating to the pipeline within the next month.

The pipeline plays a crucial role in proposals to develop a new £150 million sterling (€242 million) power station in Derry.

A private sector consortium comprising Coolkeragh employees and ESB International received planning permission last week to develop the new gas-fired power station on the outskirts of the city.

However, the consortium must commit £5 million towards the project by September as a down-payment to the group that will manufacture the new gas turbine.

Industry sources have said that the consortium is unlikely to do this unless the supporting infrastructure - the contract to build and operate the gas pipeline - is in place by that time.

The gas and electricity industry regulator, Mr Douglas McIldoon has told The Irish Times that he is confident he will be in a position to issue the licence to build the pipeline within "a matter of weeks".

He said the only outstanding issue after this will be what level of public funding the project will attract.

"We are making very good progress on drafting the licence and the only part of the jigsaw remaining after that will be the question of public funding.

"Public funding for this project would benefit the consumer because it will impact on the cost of electricity in the future," Mr McIldoon said.

"The power station will be the main customer for the pipeline, but the gas pipeline also needs the power station to provide capacity contracts as the rationale for investors.

"The question of public funding for this project is obviously an important one because the project sponsors will have to decide if they would be prepared to go ahead without a grant if public funding is not available."