The organisation has expressed its concern in a response to a consultation on the proposed protocol - which would see the GLA pair up with supermarkets to, as it describes it, "better tackle labour exploitation in the UK".
The protocol states that retailers would agree to pass information on to the GLA - or demand information from its suppliers - if the GLA suspects that workers are being exploited.
Supermarkets would also agree to take action, such as terminating a contract, if one of their suppliers is found to be complicit in any exploitation.
The GLA and supermarkets would also make regular site visits together.
But the NFU fears that the protocol - which was drawn up following discussions between the GLA and Tesco, Sainsbury's, Asda, Iceland, Marks & Spencer, Morrisons, the Co-operative and Waitrose - would keep growers/labour users out of the loop and damage their sensitive relationship with retailers.
The NFU said: "We have major concerns that a number of the clauses contained in the GLA's proposal ... would undermine relationships between retailers and their suppliers/labour users and at worst could threaten the independence of the GLA itself."
It added: "We consider that at the very minimum the GLA should ensure that the tone of the protocol is changed to ensure that it is made explicit that the protocol is to be inclusive of suppliers/labour users.
"This will require altering of the language of the document and in some cases the rewriting of a number of clauses. If this cannot be achieved then we would urge the GLA to abandon this project," concluded the NFU.
PROPOSAL CLAUSES OF PARTICULAR CONCERN
GLA "It is agreed that the retailers will provide information to the GLA where it is believed breaches of the licensing standards have occurred."
NFU "We are concerned that suppliers/labour users would not be included in the information loop between the GLA and retailers.
"It should be expected that where there are issues surrounding the use of labour, that labour users/suppliers would be privy to the same information from the GLA as retailers are."
GLA "Retailers will request that their suppliers make available to the GLA any information which may indicate that breaches of the licensing standards have occurred."
NFU "There is the potential for minor administrative errors/misunderstandings to lead to the launch of full-scale GLA operations. It is important that the GLA gathers sufficient evidence and/or intelligence before launching investigations on the basis of a single piece of information."
GLA "The GLA will work alongside retailers. The GLA would like to meet regularly with retailers so that inspection findings can be disseminated to inform best practice."
NFU "We consider that this protocol risks alienating suppliers/labour users by treating them as a part of the problem rather than as a part of the solution to stamping out the exploitation of workers."
GLA "The purpose of the visits will be to enable the retailer to appreciate the work that the GLA does, and to check that the supplier is acting responsibly in managing the use of any temporary labour and to offer advice or guidance as required."
NFU "This aspect of the protocol raises substantial issues of commercial confidentiality.
"We are concerned that during the course of joint visits retailers will become party to commercial information on a supplier, enabling the retailer to gain a commercial advantage."
- To comment on the NFU's response to the consultation contact firstname.lastname@example.org by 24 July.
The Fresh Produce Consortium (FPC) has also responded to the consultation and was due to publish its response as Grower went to press. Contact email@example.com.
The consultation ends on 31July. Visit www.gla.gov.uk.
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