The managing director of the Shell subsidiary Enterprise Energy Ireland, which is developing the Corrib gas field, has resigned, the company said yesterday.

Mr Brian Ó Catháin will be replaced as the head of Enterprise Energy by Shell executive Mr Andy Pyle. Shell acquired Enterprise Energy for €5.7 billion in April.

The Corrib field off the Co Mayo coast is the first in the State to be developed commercially since the Kinsale field in the 1970s, but it has encountered a number of planning hurdles that are likely to delay the production of gas.

In a setback last Monday, An Bord Pleanála sought a long list of supplementary information from Enterprise Energy in relation to its application to build a treatment plant on the Mayo coast.

When asked whether Mr Ó Catháin's departure was linked to that development, an Enterprise Energy spokesman said: "It's a consequence directly of the acquisition.

"It was by mutual agreement. Brian wished to leave the company," the spokesman added.

Shell's exploration and production regional director, Mr Brian Ward, said in a statement: "Brian Ó Catháin has played a highly significant role in the development of the Corrib project. I would like to thank him and wish him and his family all the very best in the future."

Mr Ó Catháin replaced Mr John McGoldrick in January 2000 following Mr McGoldrick's departure to manage the US interests of Enterprise Energy.

Mr Pyle will have overall responsibility for progressing the Corrib project, which is a joint venture with the Norwegian state firm Statoil and the US group Marathon.

He joined Shell in 1976 and has worked in project and general management in Britain, the Netherlands and the US.