The European Commission is discussing with the electricity regulator his allocation of gas network to independent power producers.
The Commission has also sought additional information from competitors and customers of the ESB on its joint venture with Statoil, which is building a power station at Ringsend, Dublin.
Meanwhile, Premier-Transmission, an Anglo-American consortium planning a cross-Border gas link between Belfast and Dublin, has suspended preliminary engineering work on its pipeline, partly due to the delay in agreeing the allocation of gas for power generation.
The electricity regulator, Mr Tom Reeves, will make the allocation of gas from the Bord Gais network to independent power plants at the end of the month. Originally planned for July, the process is necessary because Bord Gais does not have enough gas to supply all the groups which plan to build electricity generation stations.
Mr Reeves's spokesman confirmed he was in contact with the European body, but declined to comment further on the basis that the competition was still ongoing. A spokesman for the competition directorate general said the dialogue did not arise as a result of a complaint from an industry player.
Mr Reeves is also in contact with the Competition Authority about the process. This was envisaged in the legislation underlining the allocation, his spokesman said.
Industry figures have privately expressed dissatisfaction with Mr Reeves's allocation methodology, which will be based on his assessment of which groups will be "first to commission" their projects.
The delay in this complex process is one factor in the decision by Premier - owned by the US energy group KeySpan and British Gas - to suspend an engineering design contract for its pipeline. This will delay the commissioning of the project by a year until the fourth quarter in 2003, said Premier's chairman, Mr Jim Rooney.
The other factor in Premier's decision is a proposal by the Brattle consulting group, which is advising the Department of Public Enterprise, to introduce a public service levy guaranteeing uniform tariffs throughout the State on new gas networks.
Because Premier wants to build a bespoke pipeline, supplying only contracted customers, Mr Rooney described the levy as "unjust and anti-competitive".
An official at the Department of Public Enterprise said it was reviewing the indicative tariffing structure proposed by Brattle and would finalise its plans by the end of the year.
When asked whether Premier was suspending the design contract because it could not secure customers for the project, Mr Rooney said: "The company had a very good response from the marketplace and has been holding detailed discussions with at least two large industrial users of gas over the last few months.
"It is clear our potential customers will not be in a position to make a real commercial decision until the levy issue is clarified."
The ESB declined to comment on the competition directorate's analysis of its Ringsend project. The body has sought comments and documentation from five of the State-owned company's largest customers and five of its competitors - and from other parties.
The project must be sanctioned by the directorate because it has power to exempt it from EU competition rules, an exemption it requires.