P&O was one of five ferry companies fined a total of 645,000 ecus (pounds 508,000) by Brussels for illegally levying a surcharge on freight customers in 1992 to offset the effects of a devaluation in sterling.
The fines, though small, were nevertheless an embarrassment to P&O, which received the heaviest penalty, being ordered to pay 400,000 ecus. The other ferry operators fined were Stena-Sealink, Britanny Ferries, Sea France and North Sea Ferries.
Meanwhile latest figures showed that P&O's passenger numbers on the Dover- Calais route fell by just under 200,000 to 2.67 million during the key summer tourist period of July to September.
The number of tourist vehicles carried was down by just under 10 per cent to 1.15 million while there was a 3.6 per cent decline in the volume of freight handled by P&O to 295,000 units.
In the first nine months of this year passenger numbers are running at 6.765 million - nearly 900,000 down on the same period in 1995.
P&O said, however, that the rate at which it was losing business to the Channel Tunnel was slowing down. In the third quarter passenger numbers were down 7 per cent year on year compared with a 12 per cent decline in the second quarter.
Investors were unsettled by the trading news. P&O's deferred shares dropped by 12.5p to 607p.
Earlier this month P&O also announced that it was merging its cross-Channel ferry business with that of Stena Line in a move expected to produce pounds 75m of cost savings.
P&O has also merged its container business with Nedlloyd and acquired 100 per cent ownership of North Sea Ferries by buying out Nedlloyd's 50 per cent interest for pounds 25m.
According to reports yesterday the Malaysian shipping conglomerate, KPB, is interested in buying P&O Tankships, the group's 18-strong fleet of carriers. The ships operate in the short-sea routes around the United Kingdom and Europe, carrying refined products.