The fashion house, which usually produces all ads in-house, approached the two agencies in December to pitch for the business.
The agencies were handed the brief to create a "big idea" that will play out on television and in cinemas.
Armani has lent its support to the Product Red initiative, set up by U2 singer Bono in January to raise money for Aids in Africa.
Mother was recently appointed to the creative account for the Motorola Red campaign, which is due to be launched in August or September.
The appointment for Red was made without a formal pitch and, as part of the account, Mother will aim to raise international awareness of the charity campaign.
Armani advertising has previously courted controversy. In May 2004 its Junior brand was rapped for ad showing a child posing bare-chested. It showed a child sitting in the sand wearing only a pair of jeans and a string of beads. The child had long blonde hair and it was unclear as to whether it was a boy or a girl, although Armani Junior later said that it was a boy.
The ad racked up 74 complaints with charges that it sexualised children. The fashion company withdrew the ad after the negative feedback and said that it would never use it again.
Publicis Groupe's ZenithOptimedia currently handles media planning and buying for Emporio Armani and Giorgio Armani along with Lancome, Ralph Lauren and Cacharel.
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