Farming leaders have launched an appeal for retailers and consumers to buy more British beef and lamb.

Speaking at the opening of the NFU's Why Beef and Sheep Farming Matters campaign this week, president Peter Kendall warned a 10% reduction in livestock farming would cost the economy £400m per year, and lead to the deterioration of the countryside.

"Unless farmers' prices start to rise, British beef and lamb will become niche products," Kendall said. "I expect retailers to act and source more product."

Defra minister for sustainable food and farming Jeff Rooker backed the call, but praised efforts by the supermarkets to boost the consumption of British lamb and beef over the past six months.

"People believe brands more than the government, and it is a good thing if they are using British sourcing as a marketing tool," Rooker said. "But it must not be a flash in the pan - farmers need stability."