Zenith already handles Mars' media buying after it won the business after a pitch against the MediaCom. MediaCom is also the incumbent on the £10 million Wrigley media planning and buying account.
MediaCom has retained Wrigley's planning and online media business and has won the online media planning and buying for Mars, which was also included in the review.
The review followed the merger of Mars and Wrigley in October last year in a deal worth $23bn. The consolidated business includes media buying across Mars' confectionery, petcare and food ranges with brands including Snickers, Pedigree and Uncle Ben's, and media buying for Wrigley brands such as Juicyfruit and Airwaves.
Mars Consumer Drinks launched a low-calorie Galaxy probiotic chocolate drink in October. Its packaging uses the brand's signature chocolate brown with a splash of pink. The launch will be supported by TV ads from the middle of next month.