The Heartbrand range, which is marketed in the UK as Wall's, will be divided into two parts: the "take home" retail range and the "impulse" individual ice-cream brands.
DDB has been appointed to create advertising for the Heartbrand dessert range that includes Viennetta, Carte D'Or and Breyers Carb Smart, its low-fat range.
Lowe will inherit the "impulse" ice-cream brands, which include Magnum, Cornetto and Solero. The Ben & Jerry's account will remain with Fallon.
The appointment follows a global pitch that was called last year by Simon Clift, the chief marketing officer for Unilever (Campaign, 26 July 2007).
McCann, which has held a place on Unilever's roster for more than 20 years and has worked on all of Unilever's Heartbrand accounts, pitched against DDB and Lowe, two of Unilever's existing roster networks.
The news contradicts earlier reports that Lowe was set to inherit the entire business from McCann.
DDB and Lowe declined to comment. Unilever did not return calls.