ASDA has pledged to increase its fresh pork sales to 80 per cent British by next year.

The National Pig Association (NPA) welcomed the news saying British pig farmers face losses of around £150m in 2016 as a result of low prices caused by Europe’s frozen-pork mountain.

Asda also plans to switch all of its own-brand sausages to British pork by July, in order to improve quality.

Dr Zoe Davies, NPA chief executive, said if Asda moved quickly it would help keep the British pig sector relatively intact at a time when real-term prices are at their lowest for 16 years.

According to the industry’s bi-monthly PorkWatch survey, British fresh pork on Asda's shelves increased three per cent to 59 per cent in January compared with November.

Richard Lister, NPA chairman, said: "We are sure by promoting the quality of British pork, ASDA will grow pork sales across all its stores, particularly as a mid-week convenience food.

"Tangible support like this will encourage our members to stay in production until the price we receive once again covers our costs of production."

Pig prices are currently at their lowest since 2008 and at their lowest in real terms since 2000. The slump, which is now in its second year, is caused by two Russian trade embargoes causing a build-up of European Union pork in cold stores, and the strength of sterling against the euro, making continental imports difficult for some high street retailers to resist.

Uniquely, 40 per cent of the British pig herd is outdoor-reared, which is a major differentiation when compared with European Union pig production methods.

Animal welfare standards in Britain are higher than in most other countries – the use of sow stalls is banned in Britain, while sows in most other European Union countries are still kept in stalls for up to four weeks at a time.

Only about 40 per cent of pork and pork products consumed in Britain come from British pigs. The most popular cuts – back bacon, chops and steaks, gammon and ham – are under-produced domestically, whilst the less popular cuts of shoulder, belly and offal are over-produced.

About 25 per cent of home-produced pork is exported, mainly those cuts less popular with British consumers.