On Wednesday, NFU President Meurig Raymond issued a scathing criticism of Tesco, after the retailer chose to promote New Zealand lamb, in spite of sourcing commitments made in the wake of the horsemeat scandal in 2013.

Tesco was at the heart of the scandal when it broke in January last year, and subsequently took out full page adverpologies in national newspapers, claiming the horsemeat debacle would mark a turning point in sourcing policy.

This week though, Raymond described the retailer's decision to heavily promote New Zealand lamb in the middle of the prime season for British lamb as "ridiculous," given previous commitments the supermarket has made. The farm union wrote to all supermarkets last week to highlight that spring-born lamb is now in peak season, while southern hemisphere lamb, born around a year ago, is currently at the end of its season.

The NFU president commented, "Tesco stated yesterday that 'With the large demand for lamb we cannot always guarantee consistent UK stock.' I find this comment almost as ridiculous as last September's statement from Tesco that British lamb was 'not in season at the moment in the UK.' I am angry and disappointed that this comes only 18 months after giving such positive undertakings on its sourcing and supply chains for red meat.

The NFU claims that the retailer is failing to live up to commitments made by CEO Philip Clarke at the NFU Conference last year; Clarke said that Tesco would seek to support UK agriculture and wished to shorten the supply chain, in light of the fallout from the food labelling scandal.

Karel Williams, a professor at Manchester business school said the scandal was portrayed not as a food safety issue but as one of "mafia fraud" and lack of food testing. However, Wiliams said, "This is both naive and a distraction. The problem is long and constantly shifting adversarial supply chains, where processors are buying in on price and the delivery by 40 tonne chiller truck comes from somewhere different each week."

He argued that horsemeat and other issues are inevitable in 'buyer led organisations' "which are actually only responsible for producing a small proportion of what they sell;" the way in which many major supermarkets operate.

Meurig Raymond added on Wednesday, "The figures speak for themselves. The UK was self-sufficient in lamb last year and lamb numbers are even higher this year. We have more than enough lamb available. I believe that promoting New Zealand lamb over British, and Tesco's attempts to justify this, misleads consumers about the seasonality of lamb and sends a signal to farmers that Tesco are not prepared to promote the benefits of food produced in the UK."