The agency will work for Allied Bakeries on the Kingsmill and Allinson sliced loaf brands, as well as future new launches, current breads and rolls and grocery trade press and PR.
It will also review Allied Bakeries' internal communications and crisis management procedures.
Jo Sykes, marketing director of Allied Bakeries, said: "Biss Lancaster has done a good job for us for more than 10 years now, but we felt that we needed a fresh approach to PR as a fully integrated part of our 拢9m annual marketing spend."
Hill & Knowlton is the biggest consumer PR agency in the UK. Alison Eyles-Owen, managing director of Hill & Knowlton, said: "Bread and bakery products remain a key consumer driver right across the retail food sector, and Kingsmill, in particular, has shown how powerful branding can revitalise this category."
Kingsmill has been advertised with a string of spots starring the radio hosts and former television stars Mel & Sue.
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