Scottish energy company Ramco, which owns the Seven Heads gas field off the Cork coast, said talks with a possible buyer had ended. The shares closed down 3p, or 7.6 per cent, at 36.5p (€53) following the announcement yesterday.

Ramco's shares had jumped by almost 50 per cent in February when the company's management said it was in discussions with an unnamed bidder about a possible offer. The company said yesterday its board will make a further announcement within the next week after "discussions with the prospective offeror".

The Aberdeen, Scotland-based company, which also has sites in Bulgaria and Montenegro, has suffered production problems at its flagship Seven Heads field, and in 2003 wrote off its interest in the site, a decision it described in January as the "appropriate treatment."

A review of the company's operations published at the beginning of this year showed that the Seven Heads site was more compartmentalised than first thought, meaning less gas-bearing rock was available than initially forecast.

The small size of the compartments has made draining the chambers difficult and has led to a build-up of excess water, which is hampering the deliverability of the gas, the company said.

Ramco in January described the findings of the review as "extremely disappointing." However, the company's banks agreed to waive certain terms of its financing arrangements, allowing it to seek additional investment to fund more digging at the site.

In September, Ramco said its revenue jumped almost four-fold in the first half of 2004, while its loss after tax narrowed to almost £1 million, compared with £1.4 million the year-earlier period.