British pig producers are calling for the closing of a loophole which they claim allows companies to pass off foreign pork as British.
Since the beginning of the year imports of pork, ham and bacon have risen by almost a third.
Most British pig meat is produced to far higher standards - both in terms of quality and welfare - than in other European countries.
The National Pig Association, which represents British pig farmers, claims shoppers mistakenly believe pork products are British because the companies that make them do not have state where the meat came from before it was processed.
The Association's chairman Stewart Houston said firms are exploiting the fact that they have very British names.
Country of origin
"A company can be using British meat to produce products but may also be using foreign meat .
They don't have
say where's it actually from.
"The housewife looks at the name brand and assumes it must be British meat.
"These companies are not breaking any laws but they are talking advantage of a loophole."
The Association is calling for clear labelling of products to indicate the country of origin.
Mr Houston said he intends to present evidence to the Food Standards Agency which he claims shows the labelling of products in British supermarkets are misleading consumers.
Imports pressure
A spokesman for the Food Standards Agency said that while there was no law forcing companies to state on packaging the country of origin of their meat, they are supposed to do so if there is any danger of the consumer being misled.
The British Pig Executive, which represents producers and retailers in the industry, has produced a report on pig meat being imported into the UK.
The Executive, part of the Meat and Livestock Commission, claims this shows that the number of pigs being produced to UK standards in countries importing to Britain is totally inadequate to meet the volume of meat which is in fact being imported.
The results therefore suggest that the meat being produced to meet the shortfall is not being produced to British standards.
Mr Houston said the pressure of imports had cause prices to drop by 20p per kilogram and this means many farmers are only just breaking even.
UK pig farmers work to welfare standards which exceed those on Continental Europe, so production costs are higher.