Non-GM soya has become a niche product, and the supply chain is no longer equipped to keep it segregated, industry sources have warned.

A majority of UK supermarkets still specify non-GM soya feed for both broilers and layers, despite not requiring this for other livestock.

It is understood that the NFU and other industry bodies have written to retailers calling for a change in policy.

Celeres, a data provider to the Brazilian government, has reported that 88% of its 82m tonne soya crop is now GM.

Duncan Priestner, chairman of the NFU poultry board, said that non-GM had become a niche product. “We are now in the position the industry warned was coming.

“Exporting facilities have not kept up with demand and segregation is difficult. This means that the UK poultry industry is being charged a premium for a product whose integrity is deteriorating.

“Non-GM no longer stacks up for growers in terms of the economics, sustainability or global demand.”

A spokeswoman for Cargill, which imports around 65% of the UK’s non-GM soya, said that, as a result of an increased GM crop in Brazil and the strain on resources that this presents, serious concerns were being raised about the continuity of supply to the UK market.

“Cargill is very aware and, alongside our customers, is currently looking at the potential impact,” she added.

Martin Humphrey, sales director at Humphrey Feeds said that, while many integrators were covered until next harvest, spot supply was difficult.

“Whereas it may be possible to buy the odd small quantity, you would be unable to buy the rest of requirement up until the next harvest.”

He cited a £80-90/t premium on non-GM soya, but warned that if supermarkets reversed their policy, they may seek to claw back any savings.