AAK UK, the leading supplier of edible oils and fats, is warning manufacturers not to fall into the "claims trap" when buying sustainable palm oil products.

The refiner, which imported Europe's first batch of certified sustainable palm oil in 2008, is concerned about the sell-and-run supply of material, which is sold to manufacturers without advice on the international restrictions on its use.

Martin Craven, managing director of AAK UK, said the Roundtable on Sustainable Palm Oil (RSPO) has strict rules governing claims that can be made about using sustainable palm oil, but many buyers risk falling foul of them through a lack of advice from the supplier - in turn, harming the credibility and efforts of the sustainable palm oil movement.

"It is important to make clear that any user of RSPO-certified sustainable palm oil must be a member of the RSPO if they want to tell their customers and stakeholders about their use of sustainable palm oil," said Craven.

"The rules exist to maintain the integrity of the system, and yet this is not always made clear from the start by suppliers. All parties of the supply chain - including the manufacturer - must now be RSPO members and go through the full audit and certification process in order to use sustainable palm oil and make claims about it. Otherwise, the palm oil they are buying is essentially no longer classed as RSPO-certified sustainable.

"There is an onus on the supplier to inform and support customers. It's not right for a supplier to sell and run, leaving their customers to find out the truth when they've already invested in marketing, packaging, policy documents and CSR statements.

"In my opinion, any supplier that sells sustainable palm oil without guiding and supporting the customer in relation to its use is selling only half a product."

In May, the RSPO introduced a trademark that can be displayed by manufacturers and retailers using RSPO-certified sustainable palm oil, but only if their products meet stringent criteria concerning sustainable content.