Irish-based exploration company Island Oil and Gas plc says a test on the company's first well in the Celtic Sea has been a success.

Island Gas & Oil, the Irish exploration group which has a stake in the Seven Heads gas field off the Cork coast, has reported a small pre-tax loss of Stg£33,000 for the half year to January 31, 2006.

RAMCO Energy shares plunged by more than 55% yesterday after the company announced it is experiencing severe production difficulties at the Seven Heads gas field off Cork.