The BBC's Wyre Davies: "The biggest ever fine for an oil spill in British waters"

Milford Haven Port Authority will have to pay �4m after accepting responsibility for the widespread damage which followed the incident.

Judge Mr Justice Steel, at Cardiff Crown Court, said a "substantial" penalty had to reflect, genuine and justified public concern at the incident.

Bob Sinkinson reports from Cardiff Crown Court

The fine is the heaviest penalty ever made in a pollution prosecution in a UK court, four times the previous record.

The widespread pollution led to a clean-up operation of beaches costing �60m - it is estimated that the whole incident cost almost twice that amount.

Ted Sangster: Fine is "a serious blow"

The port, which had pleaded guilty to an offence of causing pollution under the Water Resources Act, will also pay �825,000 prosecution costs by agreement.

The port authority general manager Ted Sangster described the fine as "a serious financial blow" and said legal advisers were considering an appeal.

The port, with 200 employees and current reserves estimated at �33m, has already paid for a �1.3m safety review and its legal bill is put at �1.7m.

The government's Environment Agency, which brought the prosecution, called it "a good day for those who are concerned about the environment".

And Friends of the Earth welcomed the judge's sentence although its spokesman in Wales, Gordon James, said the fine was a tiny fraction of the cost of a disaster.

Wales Correspondent Wyre Davies: "It cost an extimated �100m in total"

More than 72,000 tonnes of oil poured into the sea after the Norwegian-owned tanker ran aground at the entrance to Milford Haven in February, 1996.

The accident caused severe damage to the surrounding coast, which forms part of a national park.

The court was told it happened because of the "careless" navigation of a port authority pilot who had never before attempted to take a vessel of similar size into the harbour close to low tide.

The pilot, an employee of the authority, was not prosecuted - the judge said he was too inexperienced and that the task should have been carried out by two pilots with specific local knowledge.

'Sketchy' training

He said it was significant that the port authority had reviewed its grading, training and examination of pilots following the Sea Empress grounding, and said before the incident some aspects of the system were "sketchy".

It took six days to free the vessel, but environmental damage along 120 miles of Welsh coastline was less severe than some had feared.

The effect of the spill devastated wildlife

This was due in some part to the efficiency of the clean-up operation, involving 950 people.

The impact of the spill, though dramatic, does now seem to have been short-lived. Wildlife appears to be recovering, even though some species are taking a long time to re-establish themselves in their former numbers.