Mr Owen Lamont has resigned as managing director of NTL Northern Ireland, a subsidiary of the Anglo-American telecoms giant which acquired the former Telecom Eireann cable company Cablelink for £535 million (€679.3 million) last summer.

NTL declined to comment on reports yesterday that it was considering a bid for Esat Telecom, which is fighting a $1.9 billion hostile bid by the state-owned Norwegian firm Telenor. However, the company is understood to be considering an approach by Esat.

Mr Lamont, who has led the firm in Ireland since 1995, will remain with the company in an advisory capacity. He is leaving to start his own Internet-based firm.

Speaking yesterday, he said his departure was "perfectly amicable" and his new company would not compete with with NTL.

Stating that his proposed business would "enable companies to use the web more effectively for e-business and e-commerce", Mr Lamont declined to reveal the exact nature of the venture. "I can only find four or five other firms in the world who are doing this. There's an early mover advantage, which is why I'm being coy," he said.

Mr Lamont said he would be seeking investment of up to $20 million from various sources to get the firm up and running. If this was not forthcoming, he said he would fund the investment himself. The venture would focus initially on a small number of very large corporate customers worldwide.

He expected to have a core management team in place within "two to three weeks". Three people had already committed to join the venture, he said, adding that the company would have the potential to employ up to 200 people in its initial phase.

Mr Lamont's term as president of the Northern Ireland Chamber of Commerce will not be affected by his departure from NTL. His term of office expires in April.