British farmers say cheaper New Zealand lamb is costing them about $55 for each animal they sell and they can't compete.
The National Sheep Association said supermarkets are opting for New Zealand imports over British lamb at a time when sheep farmers are struggling.
The association said that's a bitter blow when farm gate prices have dropped by more than a fifth in the last year because of rising production costs.
It is asking supermarkets to support the domestic lamb sector.