Morrisons is understood to be asking for suppliers for more support for its promotions as competition in the grocery sector intensifies.
Morrisons highlights that changes under the new management team, headed by Marc Bolland, have seen the business expand both sales and profits.
One supplier said the move reflected concerns that the grocer was falling behind rivals in terms of promotional activity, which is part funded by their suppliers.
Morrisons said: “We are strong supporters of British producers and farmers, and we have always enjoyed good relationships with our suppliers. Any recent negotiations have been part of business as usual.”