Agencies believed to include Starcom Group, OMD UK and Universal McCann have all been invited to pitch against the incumbent Vizeum, formerly BBJ, for the £10m account.
Briefs will be sent out later this month with pitches planned for the beginning of next year. Media auditing firm Billetts is involved in the review.
RHM produces brands including Hovis, Mother's Pride, Sharwoods, Bisto, Mr. Kipling and Saxa.
The review follows a series of management changes within the marketing department at RHM's bread and grocery division, Centura, earlier this year.
Ginny Knox, group marketing director of RHM, is also managing director of the division. She appointed Sharwood's head of marketing Sue Knight as brands director.
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