The chief executive of Shannon Development, Mr Paul Sheane, announced his resignation from the company yesterday after spending eight years in the position.

Mr Sheane was unavailable for comment last night but boardroom differences over policy direction are understood to have preceded his departure.

According to a statement issued by Shannon Development, he is leaving the company "to pursue other interests".

One source said that Mr Sheane (48), had been having problems with other board members for a number of months. Mr Sheane has been with Shannon Development since 1980 and prior to his appointment as chief executive in 1992 was responsible for industrial development within the company.

Mr Kevin Thompstone, the assistant chief executive, was appointed acting chief executive, effective from yesterday.

Mr Liam McElligott, chairman of Shannon Development, said that under Mr Sheane's direction, the company, which is the regional development authority for the mid-west region, including south Offaly and north Tipperary, had become self-financing from a position where one quarter of its funding came from the Exchequer.

"This is achieved mainly through revenues generated by its heritage, tourism, property management, investment and consultancy activities," he said.

The industrial estates at Shannon and Raheen, Limerick, and the National Technological Park (NTP) at Plassey are the company's main sources of revenue. The expansion of Raheen and the development of the NTP occurred over the past 10 years.

Tourism is Shannon Development's other main activity. Its subsidiary, Shannon Heritage, runs the Bunratty Folk Park and the medieval banquets at Bunratty Castle. It was recently revealed that the subsidiary's pub, the medieval-themed Castle Tavern, near King John's Castle in Limerick, was losing £3,000 a week after it was set up at a cost of £1.75 million (€2.22 million) two years ago.