In his speech, Nick Herbert will commit to creating an ombudsman as a dedicated unit in the Office of Fair Trading.
The speech — which was released to HW yesterday — calls for effective enforcement of a code of practice outlawing unacceptable practices such as retrospective discounting.
Herbert said: "Supermarkets deliver real benefits but some aspects of the way they treat their suppliers can harm consumers as well as producers. We have a new code of practice which outlaws unacceptable practices such as retrospective discounting, but this isn't worth the paper it is written on without effective enforcement.
"The Conservatives are clear: we will introduce an ombudsman to curb abuses of power which undermine our farmers and act against the long-term interest of consumers. As the Competition Commission has made clear, failure to do so could result in reduced investment by suppliers, lower product quality, and less product choice, with potentially higher prices in the long run. It is time to act."
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