Pig producers have threatened to picket supermarkets' regional distribution centres over the poor returns they are getting.

Farmers belonging to direct action body the Pig Industry Support Group say that rising costs are already making life intolerable, and allege that retailers have been putting pressure on suppliers to provide them with even cheaper meat.

Spokesman John Rowbottom said: "Last year the pigmeat price was £1.10/kg. It's now about £1/kg and there are rumours it's going to go even lower. There's terrific pressure from the retailers. They're even talking about cancelling contracts."

He added: "If we take direct action against depots, we'll be looking to do it in Scotland, East Anglia and Yorkshire."

This week PISG activists have been visiting supermarkets up and down the country placing stickers on imported pork in a bid to highlight the fact that pig farming rules on confinement are tougher in the United Kingdom than in the rest of the European Union.