Lawyers for one of the biggest wildlife charities in the world have intervened over plans to build a huge megafarm in a Norfolk village, claiming elements of the scheme are "unlawful".

The Word Wide Fund for Nature (WWF) has submitted a letter to West Norfolk Council (WNC), arguing the environmental impact of the farming complex in Methwold and Feltwell has not been properly assessed.

Cranswick, the food company, wants to construct two sites housing 14,000 pigs and 870,000 chickens on land straddling the two villages, which would be one of the biggest facilities in Europe.

The proposed plans for the two connected sites in Methwold and FeltwellThe proposed plans for the two connected sites in Methwold and Feltwell (Image: West Norfolk Council)

The food firm says it will be a modern farming facility producing affordable food to high animal welfare standards.

However, it has faced a swell of opposition from locals, environmental groups and animal welfare charities and the WWF's intervention is the latest attempt to oppose the farms.

Jake White, head of legal advocacy at WWF, has called the two environmental statements submitted by the food firm "unlawful" as they "fail to provide the public and WNC with full knowledge of the environmental costs of the projects".

Villagers in Methwold and Feltwell are concerned about the effect the megafarm will have on their livesVillagers in Methwold and Feltwell are concerned about the effect the megafarm will have on their lives (Image: Denise Bradley)

He highlights a number of factors that WWF believes have been omitted or not properly assessed in the environmental statements.

This includes the effect it would have on climate due to its carbon emissions, the cumulative effects of intensive farming sites in the region and the risk of nutrient pollution and harm to water quality. The site is situated close to groundwater sources and rare chalk streams.

READ MORE: Norfolk villagers wage long war against 'smelly farm'

Thetford & Brandon Times: Cranswick hopes to knock down the disused sheds and build 14 pig 'finishing' buildings at the siteCranswick hopes to knock down the disused sheds and build 14 pig 'finishing' buildings at the site (Image: Owen Sennitt)

It comes as Cranswick is conducting a third assessment into the extent of the pollution the farms would cause.

It says it is working with the council and specialist advisors to finalise its planning application, which will address the concerns raised by WWF and plans to issue a further update soon.

The controversy over the environmental statements delayed a decision on the scheme.

It is expected that WNC planners will assess the bid by late autumn.