He fears some retailers will be tempted to import some of the German pork that German shoppers are currently refusing to buy because of dioxin fears.

Britain already imports around 100,000 tonnes of German pigmeat a year, an increasing amount as bacon.

Even if they don't directly buy more German pig meat, retailers may be tempted to buy more Dutch pigmeat, which is falling in price as a result of the growing glut of German product.

British pig-keepers are already losing money. A glut of cheap imported pigmeat could finish some off, at a time when cull sow prices are down, because of the crisis of confidence in Germany, which is Europe's biggest market for pork and pork products.

New BPEX figures for English pig farms show a total cost of production, including depreciation and finance charges, of 164p, against which pig-keepers are receiving only 138p a kilo.

"The thing that worries us most is that if you take out those depreciation and finance charges, you are still looking at a cost of production of 144p, which means we are already in a cash negative position, and that is really hurting," said Mick Sloyan at yesterday's NPA Producer Group meeting.

The main short-term concern was that a knock-on effect from Germany would undermine the pig price, he said. "As we know, there is a potential for retailers, when they know pigmeat is going cheap to want to get a piece of it.

"We must be very vigilant to make sure retailers do not exploit the current situation, using cheap imported product in their price wars. We must not let them drive the price down, because as we know price will go down a lot faster than it will come up."

He said the situation was now so bad on the continent, the European Commission would have to offer help in the form of storage aids.

"I know some people get a bit nervous about aids to private storage but by and large if they are designed well, there is an export element so if pigmeat goes into storage it can easily find its way off the European Union market when it is released."